Poultry Processing (United States) — NAICS 311615

A Histometrics industry primer for public-market and private investors.

NAICS is the North American Industry Classification System, the federal government's standard code for industries. Code 311615, Poultry Processing, covers the businesses that turn live chickens, turkeys, and other birds into the packaged meat sold at grocery stores, restaurants, and abroad.

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1. Overview

Poultry processing is the slaughtering and packing end of America's largest meat business. Chicken is the number-one protein Americans eat — roughly 100 pounds per person a year [4][5] — and this industry is where live birds become boneless breasts, wings, nuggets, and whole roasters. It is a high-volume, commodity-cost business: processors buy grain, grow birds, kill and cut them, and sell the meat, earning a spread that swings with feed prices and wholesale chicken prices.

Why an investor cares: it is one of the few food industries where a handful of very large, industrial operators run the whole chain, so scale, cost control, and disease management decide who wins. Returns are cyclical — fat in years when feed is cheap and chicken prices are high, thin when the reverse holds [23].

Public vs. private ways in. Only a slice of this industry trades publicly. Tyson Foods and Pilgrim's Pride are listed U.S. companies with large chicken operations, and Brazil's JBS (Pilgrim's majority owner) now trades in New York too [8][9][10]. But several of the biggest processors — Perdue, Koch Foods, Wayne-Sanderson, Mountaire — are privately held, so much of the industry is reachable only through private ownership, private credit, or the farmland and contract-grower economy that feeds it [6].

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2. What it is and how it is structured

Scope. NAICS 311615 is establishments that (1) slaughter poultry and small game and/or (2) prepare processed poultry meat and byproducts — chickens, turkeys, ducks, geese, and similar birds, cut and packaged fresh, frozen, or cooked [24]. Products include cut-up parts, deboned meat, poultry hot dogs, luncheon meats, and further-processed items such as nuggets, tenders, and patties. In practice the industry is overwhelmingly broiler chickens (young meat chickens), with turkey a distant second.

What it excludes (important, because the "chicken industry" people picture is bigger than this one code):

• Raising the live birds — broiler and turkey farming — sits in agriculture codes (NAICS 112320 broiler/meat-type chicken farming; 112330 turkey farming), not here.
• Animal (except poultry) slaughtering is NAICS 311611; rendering fat, bone, and scrap is NAICS 311613; processing poultry into baby food or pet food is classified elsewhere [24].
• Eggs are a separate business — table-egg layers are farm production (NAICS 112310), not poultry processing. A public name like Cal-Maine Foods is an egg producer, not a 311615 processor.

Ownership mix and the integration model. This is the defining feature. Nearly all U.S. broilers are produced under vertical integration: the processing company owns the hatcheries, the feed mills, the trucks, and the plants, and it contracts with thousands of independent farmers ("growers") to raise the birds [13]. The company delivers day-old chicks and feed; the grower supplies the land, the barns, the labor, and the utilities, and is paid on a tournament system — a base rate adjusted up or down by how efficiently that grower's flock converts feed to weight versus neighboring growers [13]. So the processor controls the genetics, the feed, and the schedule; the grower carries much of the capital cost of the barns and the operating risk. Because live birds do not travel economically over long distances, the system is organized around regional processing complexes: USDA found that 90% of contract broilers were raised within 60 miles of their processing plant and 50% within 30 miles [25]. The federal processing-plant statistics below capture the plants, not those ~25,000 contract farms, which live in the agriculture codes.

Product mix shift. The industry has moved decisively away from whole birds. By 2011, USDA estimated that whole birds were only 12% of broiler production, cut-up parts 42%, and further-processed products 46%, versus more than 80% whole birds in the early 1960s [26]. Larger birds are generally optimized for deboning and further processing, while smaller birds serve rotisserie, quick-service, and bone-in channels.

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3. How big it is

Federal business statistics for NAICS 311615 (our ground-truth figures):

Industry-body and USDA production data give the physical picture: in 2024 U.S. processors produced about 9.33 billion broilers weighing 61.1 billion pounds live, with a farm value of roughly $45.4 billion [5]. Turkey production was 200 million birds, 6.58 billion pounds, and $3.69 billion of production value [5]. (Note the two dollar figures measure different things: the ~$90 billion Census "receipts" is the value of what plants ship — processed, cut, further-prepared meat — while the ~$45 billion is the liveweight farm value of the birds before processing [2][5].)

Undercount caveat — different from most industries. Unlike sectors dominated by tiny sole proprietors or by government, poultry processing is dominated by a few large corporations, so the establishment-based Census counts capture the plants well. What the single code hides is the rest of the integrated chain — the feed mills, hatcheries, and roughly 25,000 contract-grower farms that are counted under agriculture NAICS codes, not 311615. Read the whole "broiler complex" and the industry is materially larger than the processing code alone; the plant statistics are accurate but partial.

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4. The investable universe

Only three companies with major U.S. chicken operations trade publicly; the rest of the top tier is private. Dollar and share figures are approximate and belong here rather than in the prose above.

Public companies

Major private / other owners (ranked by ready-to-cook output) [6][29]:

• Wayne-Sanderson Farms — #3 processor (~14% of volume); a private joint venture (JV) of Cargill and Continental Grain, formed in 2022 by merging Wayne Farms with Sanderson Farms (taken private for $4.5 billion, $203/share) [11].
• Mountaire Farms — private; ~6.5% of volume [29].
• Perdue Farms — large, family-owned (~6.2% of volume; ~64 million pounds ready-to-cook weekly in 2024) [6][29].
• Koch Foods — private; ~6.0% of volume [29].
• Foster Farms (West Coast; sold to Atlas Holdings in 2022), George's, Peco Foods, Mar-Jac, House of Raeford — mid-sized privately held processors [6].

The top four processors (Tyson, Pilgrim's, Wayne-Sanderson, Mountaire) produce roughly 58% of U.S. ready-to-cook chicken by volume; the top six reach about 70% [29]. Note that this production-volume concentration is higher than the Census receipts-based CR4 (39.2%) because the latter includes all 311615 establishments (including turkey processors and smaller further-processors), not just broiler integrators [2][29].

Turkey exposure. Seaboard owns a non-controlling 52.5% interest in Butterball, which reported $2.09 billion of 2025 sales and $155 million of net income [30]. Hormel supplies additional turkey exposure through Jennie-O, though Hormel no longer reports Jennie-O as a standalone segment.

If few public plays fit your thesis, the realistic private routes are: buying or lending to a regional processor, owning the farmland and contract-grower barns that supply the integrators, or the feed-grain and equipment businesses upstream.

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5. How the money works

Owners earn a crush-style spread: the gap between the wholesale price of chicken meat and the cost of producing it, where feed is the dominant cost.

• Feed is 65–75% of the cost of a live bird, and feed is mostly corn (energy) and soybean meal (protein) [14][29]. Pilgrim's disclosed that corn, soybean meal, and wheat represented 45.9%, 33.7%, and 4.6%, respectively, of its 2025 feed costs [9]. Feed prices respond to crop yields, weather, global demand, government agricultural policy, and competing uses such as biofuels. So a processor's margin is largely a bet on the spread between grain prices and chicken prices. Cheap corn and soybeans plus firm chicken prices = fat margins; the reverse squeezes everyone [23].
• Conversion efficiency matters enormously. The key operating metric is the feed-conversion ratio — pounds of feed per pound of bird — alongside livability (survival), average weight, and days to market. Small gains, spread over billions of birds, are real money, which is why genetics, feed formulation, and grower performance are guarded closely [13].
• Product mix and "further processing" add margin. Commodity whole birds and leg quarters are low-margin and price-cyclical; branded, marinated, breaded, cooked, and food-service products (nuggets, tenders, retail-ready packs) carry higher and steadier margins. Pilgrim's U.S. prepared-food sales rose from $1.10 billion in 2024 to $1.32 billion in 2025, while fresh products remained much larger at $8.89 billion [9]. Tyson's strategy of leaning on prepared foods over raw commodity chicken is the clearest example [8].
• Plant utilization and line speed drive fixed-cost absorption. Plants want to run full; regulatory caps on how fast the kill-and-cut line can move (see Regulation) directly affect throughput per plant [15].
• Customer concentration. Consolidated retail and foodservice customers have purchasing leverage. Tyson disclosed that Walmart represented 18.7% of its consolidated fiscal-2025 sales (across all Tyson segments) [28].
• The cycle. Because birds reach market weight in only ~6–7 weeks, supply responds fast to price signals, so the industry over- and under-shoots. Tyson's chicken segment margin was 8.5% in fiscal 2025, up from 6.0% in 2024 and negative 4.5% in 2023 — driven largely by lower feed costs ($895 million in savings in 2024, another $340 million in 2025) and operating execution [28]. Pilgrim's U.S. segment achieved roughly 10.7% operating margin in 2025 [9]. But strong margins can produce oversupply: the soft late-2025 breast-meat market showed the textbook broiler cycle [23].

Bottom line: this is a commodity manufacturing business. You make money by being the low-cost producer, keeping plants full, mixing toward value-added products, and timing the feed-to-meat spread — not by pricing power over customers.

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6. What drives demand

• Domestic protein preference. Chicken is the cheapest and most popular U.S. meat; per-capita retail-weight disappearance reached 101.1 pounds in 2024 and represented 44.6% of combined red-meat and poultry disappearance, up from 80.4 pounds and 39.8% in 2012 [31]. Chicken is a share-gainer when cattle supplies are tight and beef prices spike.
• Food-service and quick-service restaurants. Chicken sandwiches, wings, and tenders anchor fast-food menus; restaurant demand and promotional cycles (e.g., the "chicken sandwich wars") move wing and breast prices.
• Exports. About 14.3% of U.S. broiler production was exported in 2024 (~$5.5 billion, 3.25 million metric tons), with Mexico by far the largest market, then Canada and China [12][31]. Exports matter especially for dark meat and paws/feet, parts U.S. consumers eat less of, so trade access shapes the value of the whole bird.
• Feed-grain economics indirectly drive supply and therefore price.

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7. Regulation

• USDA food-safety oversight. The U.S. Department of Agriculture's Food Safety and Inspection Service (FSIS) inspects every poultry plant and every bird, and sets pathogen (e.g., Salmonella) standards. This is continuous, mandatory federal inspection — a core cost and compliance burden [15]. Note: the broad FSIS proposal that would have treated certain Salmonella levels and serotypes in raw chicken and turkey as adulterants was withdrawn effective April 25, 2025; it is not current law [32]. A narrower rule covering not-ready-to-eat breaded stuffed chicken products remains a distinct matter [33].
• Line-speed rules. Under the New Poultry Inspection System (NPIS), plants can run young-chicken lines up to 175 birds per minute (bpm) (60 bpm for turkeys) — a limit that directly caps plant throughput. FSIS has kept these faster speeds via waivers and, in 2025, moved to codify them in a new rule, while dropping a requirement that plants submit worker-safety data [15].
• Worker safety (OSHA). Poultry processing is among the more hazardous manufacturing jobs; the Occupational Safety and Health Administration (OSHA) oversees repetitive-motion injuries, chemical exposure, and machine hazards. OSHA identifies musculoskeletal disorders as a continuing concern and notes risks from noise, dangerous equipment, and hazardous chemicals [20].
• Labor and immigration. Processing lines rely heavily on immigrant labor; immigration enforcement, wages, and worker-treatment scrutiny are recurring operational and reputational risks [20].
• Grower transparency. USDA's transparency rule, effective February 12, 2024, requires disclosures concerning broiler contracts and grower-ranking payment systems, including minimum annual placements and stocking density [34].
• Environmental. Plants and the grower barns they contract generate significant water use, wastewater, and manure/nutrient runoff, drawing Clean Water Act and state permitting attention. EPA withdrew its proposed tighter national meat-and-poultry effluent rule in August 2025, so that proposal is not current law; state permits and local sewer agreements can nevertheless require substantial plant-specific investment [35].
• Animal disease control. USDA's Animal and Plant Health Inspection Service (APHIS) manages highly pathogenic avian influenza (HPAI) response, including quarantine and culling — see Risks.

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8. Competitive dynamics and consolidation

The industry is moderately concentrated and steadily consolidating. Federal concentration data for 311615:

• Top 4 firms: 39.2% of receipts; top 8: 55.4%; top 20: 76.1%; top 50: 91.9% [2].
• Herfindahl-Hirschman Index (HHI): 568 — below the 1,500 threshold the U.S. antitrust agencies treat as "moderately concentrated," so on a national basis no single firm dominates [2].

But the national HHI understates real-world power because broiler complexes are regional — a processor may control most of the contract-grower opportunities within trucking distance of its plants, giving it strong local leverage over farmers even if its national share is modest [13]. USDA found that 77% of broiler growers had no more than three potential integrators in their area, and 54% had only one or two [25]. National wholesale chicken can be moderately concentrated while local grower-service markets are effectively oligopsonies. Consolidation has continued: the 2022 take-private of Sanderson Farms and its merger with Wayne Farms created a new #3 out of two large players [11].

Litigation legacy. The industry ran through a decade of antitrust and labor cases. In the broiler price-fixing civil litigation, Tyson settled for $221.5 million and Pilgrim's for $75 million, among others; Pilgrim's separately pleaded guilty to a criminal price-fixing charge and paid a ~$107.9 million U.S. Department of Justice (DOJ) fine [16]. Processors also collectively settled grower/worker wage-suppression claims for roughly $400 million [17]. Sanderson Farms was cleared by a jury in the price-fixing case [16]. These are resolved but signal an industry under close antitrust and labor scrutiny.

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9. Risks

• Feed-cost / margin cyclicality. Corn and soybean-meal prices are the single biggest swing factor; a bad crop year or export shock can flip the spread from profit to loss [14][23].
• Disease — HPAI. Highly pathogenic avian influenza has been the defining biosecurity threat since 2022. So far broilers have been far less hit than egg layers and turkeys — of ~221.7 million birds lost since 2022, about 178.8 million were laying hens and only ~13.2 million (7%) were broilers, partly because broiler complexes sit away from the worst migratory flyways [18]. But a broiler-belt outbreak, or export bans triggered by any U.S. detection, is a real tail risk.
• Trade exposure. Heavy reliance on Mexico and export markets for dark meat and paws makes the whole-bird economics vulnerable to tariffs, retaliation, and foreign health bans [12].
• Regulatory and labor. Line-speed rules, OSHA scrutiny, immigration enforcement, and environmental permitting all bear on cost and capacity [15][20].
• Grower regulation. Further changes to tournament compensation, capital-improvement demands, or Packers and Stockyards Act enforcement could transfer economics between integrators and growers [34].
• Reputational / ESG. Contract-grower economics, worker injury rates, animal-welfare campaigns, and antitrust history keep the industry under advocacy and media pressure [16][17][20].
• Commodity price weakness. The classic oversupply cycle — fast biological response to good margins — can crater prices, as the soft late-2025 breast-meat market showed [23].

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10. How to invest and the outlook

Public routes.

• Tyson Foods (TSN) — the largest and most diversified play; chicken is one of four protein segments, so it is partly a bet on Tyson's mix shift toward higher-margin prepared foods and on a chicken-margin recovery [8]. Tickers, prices, and dividend yield should be checked at time of investing.
• Pilgrim's Pride (PPC) — the closest thing to a pure-play large chicken processor, though ~82% owned by JBS, which limits free float and minority influence [9].
• JBS (NYSE) — indirect exposure to Pilgrim's plus JBS's global meat platform, for investors comfortable with a Brazil-controlled multinational [10].
• Seaboard (SEB) — exposure to Butterball (52.5% equity interest) for turkey, though Seaboard's pork, grain, and shipping operations are much larger [30].
• Broad consumer-staples or agribusiness funds hold these names without single-stock concentration.

Private routes. Because Perdue, Koch, Wayne-Sanderson, and Mountaire are private, direct exposure comes through private equity/credit in regional processors, ownership of the contract-grower farmland and poultry barns that supply integrators (an income-style real-asset play tied to grower contracts), or the upstream feed-grain, genetics, and processing-equipment businesses. Contract-grower farms provide real-estate-like cash flow but carry integrator concentration, placement, disease, utility-cost, and mandated-capital-upgrade risks; they should not be underwritten as though the grower owns the chickens or controls market pricing.

Near-term drivers to watch (forward-looking):

• The feed-vs-meat spread — corn and soybean prices against wholesale chicken — remains the master variable; cheap grain plus firm demand is the bull case, oversupply the bear case [23].
• HPAI's path — continued relative sparing of broilers supports supply; a broiler-belt outbreak or export ban is the key shock [18].
• Chicken's share gains if beef stays expensive during the tight cattle cycle, boosting relative demand [4].
• Line-speed rulemaking finalization, which could lift plant throughput and margins [15].
• Export access, especially to Mexico and China, for whole-bird economics [12].

Judgment: the long-run demand story for chicken is durable — cheapest, most-consumed U.S. protein, still gaining share — but the returns are cyclical and commodity-driven, not steady-compounder. The best-positioned owners are the low-cost, well-integrated operators with value-added product mix and strong biosecurity. Treat it as a cyclical manufacturing bet on the feed-to-meat spread, not a defensive staple.

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Sources

1. U.S. Census Bureau, County Business Patterns, 2023 (NAICS 311615: employment, establishments, annual payroll). https://www.census.gov/programs-surveys/cbp.html
2. U.S. Census Bureau, 2022 Economic Census — Concentration of Largest Firms (EC2231) (NAICS 311615: receipts, firms, CR4/CR8/CR20/CR50, HHI). https://www.census.gov/programs-surveys/economic-census.html
3. U.S. Small Business Administration, Table of Small Business Size Standards, 2023 (NAICS 311615: 1,250-employee standard). https://www.sba.gov/document/support-table-size-standards
4. National Chicken Council, Industry Statistics / Per Capita Consumption, 2024–2025. https://www.nationalchickencouncil.org/about-the-industry/statistics/
5. USDA National Agricultural Statistics Service, Poultry — Production and Value 2024 Summary, April 2025. https://esmis.nal.usda.gov/sites/default/release-files/m039k491c/ws85cd48j/q524mm00n/plva0425.pdf
6. WATT Global Media, WATT PoultryUSA 2025 Top Broiler Company Rankings (ready-to-cook weekly volume, 2024), 2025. https://www.wattagnet.com/top-poultry-companies
7. Zippia / EssFeed, Largest U.S. Poultry Companies by Market Share, 2025. https://www.zippia.com/advice/largest-poultry-companies/
8. Tyson Foods, Inc., Fourth Quarter and Fiscal 2024 Results (Chicken segment sales $16.43B; AOI $1.015B), Nov. 2024. https://ir.tyson.com/news/news-details/2024/Tyson-Foods-Reports-Fourth-Quarter-And-Fiscal-2024-Results/default.aspx
9. Pilgrim's Pride Corporation, Form 10-K, FY2025 (net sales $18.5B; U.S. segment $11.0B; JBS 82.28% ownership; feed cost breakdown; prepared-food sales). https://www.sec.gov/Archives/edgar/data/802481/000080248126000011/ppc-20251228.htm
10. MEAT+POULTRY, JBS Shares Begin Trading on the NYSE (dual listing, ticker JBS, June 2025), 2025. https://www.meatpoultry.com/articles/32034-jbs-shares-begin-trading-on-nyse
11. Cargill, Cargill and Continental Grain Complete Acquisition of Sanderson Farms ($4.5B / $203 per share; Wayne-Sanderson Farms formed), 2022. https://www.cargill.com/2022/cargill-continental-grain-complete-acquisition-sanderson-farms
12. National Chicken Council / USDA Foreign Agricultural Service, U.S. Broiler Exports 2024 (~$5.5B; Mexico, Canada, China), 2025. https://www.nationalchickencouncil.org/policy/international-trade/
13. USDA Economic Research Service, Vertical Coordination in the Broiler Industry / Lessons from the Poultry, Egg, and Pork Industries (contract growing, tournament system). https://www.ers.usda.gov/
14. Poultry feed formulation references (corn + soybean meal ~65–75% of live production cost); academic and industry sources. https://www.sciencedirect.com/science/article/pii/S1056617123000090
15. USDA Food Safety and Inspection Service, Maximum Line Speed Rates for Young Chicken and Turkey Establishments under NPIS (175 bpm; 2024–2025 waivers and rulemaking). https://www.fsis.usda.gov/policy/federal-register-rulemaking/federal-register-rules/maximum-line-speed-rates-young-chicken
16. Cohen Milstein / Food Business News, In re Broiler Chicken Antitrust Litigation (Tyson $221.5M, Pilgrim's $75M civil, Pilgrim's ~$107.9M DOJ criminal fine; Sanderson cleared), 2021–2023. https://www.cohenmilstein.com/case-study/re-broiler-chicken-antitrust-litigation/
17. ClassAction.org, Poultry Producer Wage-Suppression Settlements (~$400M), 2022–2023. https://www.classaction.org/news/poultry-producer-settlements-totaling-nearly-400m-resolve-lawsuit-over-alleged-wage-suppression-conspiracy
18. American Farm Bureau Federation, Avian Influenza Hits Turkeys and Eggs Hardest (broilers ~13.2M of ~221.7M birds lost since 2022), 2025. https://www.fb.org/market-intel/avian-influenza-hits-turkeys-and-eggs-hardest
19. Macrotrends / StockAnalysis, Tyson Foods (TSN) and Pilgrim's Pride (PPC) market capitalization, 2025. https://www.macrotrends.net/stocks/charts/PPC/pilgrims-pride/market-cap
20. OSHA, Poultry Processing — Safety and Health Topics (injury rates, musculoskeletal disorders, hazards). https://www.osha.gov/poultry-processing
21. Human Rights Watch / Southern Poverty Law Center, Workers' Rights in U.S. Meat and Poultry Plants (injury rates, immigrant labor). https://www.hrw.org/report/2019/09/04/when-were-dead-and-buried-our-bones-will-keep-hurting/workers-rights-under-threat
22. N/A — renumbered.
23. The Poultry Site / USDA ERS Livestock, Dairy, and Poultry Outlook (2025 margin cycle; feed-vs-meat spread; late-2025 oversupply), 2025–2026. https://www.thepoultrysite.com/news/2026/05/us-broiler-sector-squeezes-efficiencies-as-margins-face-pressure
24. U.S. Census Bureau, NAICS 2022 — Definition of 311615 Poultry Processing (scope and exclusions: 311611, 311613, baby/pet food). https://www.census.gov/naics/?details=31161&input=31161&year=2022
25. USDA Economic Research Service, Concentration and Competition in U.S. Agribusiness (contract grower distances, local concentration). https://ers.usda.gov/sites/default/files/_laserfiche/publications/106795/EIB-256.pdf?v=13378
26. USDA Economic Research Service, Processed products dominate U.S. broiler production (product mix shift since 1960s). https://ers.usda.gov/data-products/charts-of-note/77558
27. U.S. Bureau of Labor Statistics, Table B-1b: Employees on nonfarm payrolls by industry sector, December 2025. https://www.bls.gov/ces/data/employment-and-earnings/2025/table1b_202512.htm
28. Tyson Foods, Inc., Form 10-K, FY2025 (Chicken segment $16.8B sales, 8.5% operating margin; margin history; feed cost savings; Walmart 18.7% of sales). https://www.sec.gov/Archives/edgar/data/100493/000010049325000095/tsn-20250927.htm
29. Choices Magazine / Agricultural & Applied Economics Association, Competition in the U.S. Broiler Industry, 2025 (market shares by ready-to-cook volume; feed cost share; antitrust history). https://www.choicesmagazine.org/UserFiles/file/cmsarticle_996.pdf
30. Seaboard Corporation, Form 10-K, FY2025 (Butterball 52.5% interest; $2.09B sales; $155M net income). https://www.sec.gov/Archives/edgar/data/88121/000008812126000012/seb-20251231x10k.htm
31. USDA Economic Research Service, Livestock, Dairy, and Poultry Outlook, August 2025 (per-capita disappearance; export share). https://ers.usda.gov/sites/default/files/_laserfiche/outlooks/113151/LDP-M-374.pdf
32. USDA Food Safety and Inspection Service, Salmonella Framework for Raw Poultry Products — Withdrawal, April 2025. https://www.fsis.usda.gov/policy/federal-register-rulemaking/federal-register-rules/salmonella-framework-raw-poultry-products
33. USDA Food Safety and Inspection Service, Salmonella in Not-Ready-to-Eat Breaded Stuffed Chicken Products — Final Determination. https://www.fsis.usda.gov/policy/federal-register-rulemaking/federal-register-rules/salmonella-not-ready-eat-breaded-stuffed
34. USDA Agricultural Marketing Service, Transparency in Poultry Grower Contracting and Tournaments, effective February 2024. https://www.ams.usda.gov/rules-regulations/transparency-poultry-grower-contracting-and-tournaments
35. U.S. Environmental Protection Agency, Meat and Poultry Products Effluent Guidelines (existing rule; proposed tighter rule withdrawn August 2025). https://www.epa.gov/eg/meat-and-poultry-products-effluent-guidelines