Nucor (NUE) 10-Q 11 Aug 21 2021 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information	6 Months Ended
	Jul. 03, 2021shares
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jul. 3, 2021
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q2
Trading Symbol	NUE
Entity Registrant Name	NUCOR CORPORATION
Entity Central Index Key	0000073309
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Emerging Growth Company	false
Entity Small Business	false
Entity Current Reporting Status	Yes
Entity Shell Company	false
Entity Interactive Data Current	Yes
Title of 12(b) Security	Common Stock, par value $0.40 per share
Security Exchange Name	NYSE
Entity Incorporation, State or Country Code	DE
Document Quarterly Report	true
Document Transition Report	false
Entity File Number	1-4119
Entity Tax Identification Number	13-1860817
Entity Address, Address Line One	1915 Rexford Road
Entity Address, City or Town	Charlotte
Entity Address, State or Province	NC
Entity Address, Postal Zip Code	28211
City Area Code	704
Local Phone Number	366-7000
Entity Common Stock, Shares Outstanding	293,694,534

Condensed Consolidated Statemen

Condensed Consolidated Statements of Earnings - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 03, 2021	Jul. 04, 2020	Jul. 03, 2021	Jul. 04, 2020
Income Statement [Abstract]
Net sales	$ 8,789,164	$ 4,327,306	$ 15,806,304	$ 9,951,643
Costs, expenses and other:
Cost of products sold	6,315,661	3,949,347	11,710,364	8,944,416
Marketing, administrative and other expenses	387,070	142,017	678,194	295,409
Equity in (earnings) losses of unconsolidated affiliates	(19,403)	14,078	(32,642)	14,901
Losses on assets	44,308	5,000	50,970	292,846
Interest expense, net	35,780	35,807	75,424	76,717
Costs, expenses and other, total	6,763,416	4,146,249	12,482,310	9,624,289
Earnings before income taxes and noncontrolling interests	2,025,748	181,057	3,323,994	327,354
Provision for income taxes	454,289	47,904	765,021	139,822
Net earnings	1,571,459	133,153	2,558,973	187,532
Earnings attributable to noncontrolling interests	64,591	24,272	109,673	58,320
Net earnings attributable to Nucor stockholders	$ 1,506,868	$ 108,881	$ 2,449,300	$ 129,212
Net earnings per share:
Basic	$ 5.05	$ 0.36	$ 8.14	$ 0.42
Diluted	$ 5.04	$ 0.36	$ 8.13	$ 0.42
Average shares outstanding:
Basic	296,817	302,921	299,359	302,915
Diluted	297,529	302,933	299,738	302,932

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Jul. 03, 2021		Jul. 04, 2020		Jul. 03, 2021		Jul. 04, 2020
Statement Of Comprehensive Income [Abstract]
Net earnings	$ 1,571,459		$ 133,153		$ 2,558,973		$ 187,532
Other comprehensive income:
Net unrealized income (loss) on hedging derivatives, net of income taxes of $2,600 and $200 for the second quarter of 2021 and 2020, respectively, and $3,000 and $(600) for the first six months of 2021 and 2020, respectively	8,204		757		9,203		(1,499)
Reclassification adjustment for settlement of hedging derivatives included in net income, net of income taxes of $0 and $900 for the second quarter of 2021 and 2020, respectively, and $100 and $1,600 for the first six months of 2021 and 2020, respectively	196	[1]	2,543	[2]	697	[1]	4,599	[2]
Foreign currency translation gain (loss), net of income taxes of $0 for the second quarter and first six months of 2021 and 2020	21,431		23,491		35,232		(40,970)
Net current-period other comprehensive income (loss)	29,831		26,791		45,132		(37,870)
Comprehensive income	1,601,290		159,944		2,604,105		149,662
Comprehensive income attributable to noncontrolling interests	64,591		24,272		109,673		58,320
Comprehensive income attributable to Nucor stockholders	$ 1,536,699		$ 135,672		$ 2,494,432		$ 91,342
[1]	Includes $196 and $697 of accumulated other comprehensive income (loss) reclassifications into cost of products sold for net losses on commodity contracts in the second quarter and first six months of 2021, respectively. The tax impact of those reclassifications was $0 and $100 in the second quarter and first six months of 2021, respectively.
[2]	Includes $2,543 and $4,599 of accumulated other comprehensive income (loss) reclassifications into cost of products sold for net losses on commodity contracts in the second quarter and first six months of 2020, respectively. The tax impact of those reclassifications was $900 and $1,600 in the second quarter and first six months of 2020, respectively.

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Comprehensive Income (Parenthetical) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 03, 2021	Jul. 04, 2020	Jul. 03, 2021	Jul. 04, 2020
Statement Of Comprehensive Income [Abstract]
Net unrealized (loss) income on hedging derivatives, tax	$ 2,600	$ 200	$ 3,000	$ (600)
Reclassification adjustment for settlement of hedging derivatives included in net income, tax effect	0	900	100	1,600
Foreign currency translation (loss) gain tax	$ 0	$ 0	$ 0	$ 0

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Jul. 03, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 2,722,656	$ 2,639,671
Short-term investments	398,409	408,004
Accounts receivable, net	3,399,076	2,298,850
Inventories, net	5,240,750	3,569,089
Other current assets	295,048	573,048
Total current assets	12,055,939	9,488,662
Property, plant and equipment, net	7,235,536	6,899,110
Restricted cash and cash equivalents	84,350	115,258
Goodwill	2,241,558	2,229,672
Other intangible assets, net	627,201	668,021
Other assets	750,998	724,671
Total assets	22,995,582	20,125,394
Current liabilities:
Short-term debt	100,686	57,906
Current portion of long-term debt and finance lease obligations	12,027	10,885
Accounts payable	2,204,137	1,432,159
Salaries, wages and related accruals	850,396	462,727
Accrued expenses and other current liabilities	712,704	664,183
Total current liabilities	3,879,950	2,627,860
Long-term debt and finance lease obligations due after one year	5,275,496	5,271,789
Deferred credits and other liabilities	1,130,485	993,884
Total liabilities	10,285,931	8,893,533
Nucor stockholders' equity:
Common stock	152,061	152,061
Additional paid-in capital	2,117,155	2,121,288
Retained earnings	13,550,406	11,343,852
Accumulated other comprehensive loss, net of income taxes	(73,729)	(118,861)
Treasury stock	(3,491,915)	(2,709,675)
Total Nucor stockholders' equity	12,253,978	10,788,665
Noncontrolling interests	455,673	443,196
Total equity	12,709,651	11,231,861
Total liabilities and equity	$ 22,995,582	$ 20,125,394

Condensed Consolidated Statem_4

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jul. 03, 2021	Jul. 04, 2020
Operating activities:
Net earnings	$ 2,558,973	$ 187,532
Adjustments:
Depreciation	362,492	349,691
Amortization	41,858	42,165
Stock-based compensation	66,729	39,101
Deferred income taxes	102,367	90,515
Distributions from affiliates	180	2,000
Equity in (earnings) losses of unconsolidated affiliates	(32,642)	14,901
Losses on assets	50,970	292,846
Changes in assets and liabilities (exclusive of acquisitions and dispositions):
Accounts receivable	(1,093,021)	264,424
Inventories	(1,673,962)	464,004
Accounts payable	726,649	(272,910)
Federal income taxes	290,287	26,145
Salaries, wages and related accruals	385,265	(142,388)
Other operating activities	97,041	(8,058)
Cash provided by operating activities	1,883,186	1,349,968
Investing activities:
Capital expenditures	(702,378)	(777,317)
Investment in and advances to affiliates	(169)	(9,756)
Disposition of plant and equipment	10,665	17,652
Acquisitions (net of cash acquired)	300	794
Purchase of investments	(357,917)	(222,500)
Proceeds from the sale of investments	367,512	275,067
Other investing activities	587	1,132
Cash used in investing activities	(681,400)	(714,928)
Financing activities:
Net change in short-term debt	42,780	2,208
Proceeds from long-term debt, net of discount		1,074,995
Repayment of long-term debt		(77,150)
Bond issuance related costs		(6,250)
Proceeds from exercise of stock options	128,800
Payment of tax withholdings on certain stock-based compensation	(64,416)	(17,263)
Distributions to noncontrolling interests	(97,196)	(62,965)
Cash dividends	(246,539)	(245,619)
Acquisition of treasury stock	(916,145)	(39,499)
Other financing activities	(5,072)	(4,645)
Cash (used in) provided by financing activities	(1,157,788)	623,812
Effect of exchange rate changes on cash	8,079	(4,268)
Increase in cash and cash equivalents and restricted cash and cash equivalents	52,077	1,254,584
Cash and cash equivalents and restricted cash and cash equivalents - beginning of year	2,754,929	1,534,605
Cash and cash equivalents and restricted cash and cash equivalents - end of six months	2,807,006	2,789,189
Non-cash investing activity:
Change in accrued plant and equipment purchases	$ 44,754	$ (25,897)

Basis of Interim Presentation

Basis of Interim Presentation	6 Months Ended
	Jul. 03, 2021
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Basis of Interim Presentation	1. Basis of Interim Presentation The information furnished in this Item 1 reflects all adjustments which are, in the opinion of management, necessary to a fair statement of the results for the interim periods presented and are of a normal and recurring nature unless otherwise noted. The information furnished has not been audited; however, the December 31, 2020 condensed consolidated balance sheet data was derived from audited financial statements but does not include all disclosures required by accounting principles generally accepted in the United States of America. The unaudited condensed consolidated financial statements included in this Item 1 should be read in conjunction with the audited consolidated financial statements and the notes thereto included in Nucor’s Annual Report on Form 10-K for the year ended December 31, 2020.

Inventories

Inventories	6 Months Ended
	Jul. 03, 2021
Inventory Disclosure [Abstract]
Inventories	2. Inventories Inventories consisted of approximately 48% raw materials and supplies and 52% finished and semi-finished products at July 3, 2021 (42% and 58%, respectively, at December 31, 2020). Nucor’s manufacturing process consists of a continuous, vertically integrated process from which products are sold to customers at various stages throughout the process. Since most steel products can be classified as either finished or semi-finished products, these two categories of inventory are combined.

Property, Plant and Equipment

Property, Plant and Equipment	6 Months Ended
	Jul. 03, 2021
Property Plant And Equipment [Abstract]
Property, Plant and Equipment	3. Property, Plant and Equipment Property, plant and equipment is recorded net of accumulated depreciation of $10.20 billion at July 3, 2021 ($9.86 billion at December 31, 2020). Nucor reviews its natural gas well assets for impairment if and when circumstances indicate that a decline in value below their carrying amounts may have occurred. Nucor last assessed its proved producing natural gas well assets in the fourth quarter of 2020 due to the continued low-price natural gas pricing environment. After completing its assessment, Nucor determined that as of such time there were no impairments of any of its three groups of proved well assets. C Therefore, it is reasonably possible that u The combined carrying value of the three groups of wells was Nucor owns a 49% leasehold interest in unproved oil and natural gas properties covering approximately 54,000 acres in the South Piceance Basin located in Colorado. Nucor is subject to forfeiture of a portion of its leasehold interest in these properties if we do not drill new wells within various contractually specified time periods. A decision to not develop a portion of these properties within the specified time periods would likely result in a partial asset impairment in the future. Nucor has full discretion on its participation in all future drilling capital investments related to the leasehold interest. In the second quarter of 2021, Nucor made the decision that it would not develop a portion of its unproved oil and natural gas properties (“Portion A”) within the contractually specified time period related to Portion A. As a result of this decision, the Company will forfeit its leasehold rights for Portion A. The Company recorded a charge of $42.0 million . The carrying value of the remaining portions of unproved oil and natural gas properties was $96.0 million at July 3, 2021.

Goodwill and Other Intangible A

Goodwill and Other Intangible Assets	6 Months Ended
	Jul. 03, 2021
Goodwill And Intangible Assets Disclosure [Abstract]
Goodwill and Other Intangible Assets	4. Goodwill and Other Intangible Assets The change in the net carrying amount of goodwill for the six months ended July 3, 2021 by segment was as follows (in thousands): Steel Mills Steel Products Raw Materials Total Balance at December 31, 2020 $ 612,470 $ 887,625 $ 729,577 $ 2,229,672 Acquisitions 705 - - 705 Other - (129 ) - (129 ) Translation - 11,310 - 11,310 Balance at July 3, 2021 $ 613,175 $ 898,806 $ 729,577 $ 2,241,558 Nucor completed its most recent annual goodwill impairment testing during the fourth quarter of 2020 and concluded that as of such time there was no impairment of goodwill for any of its reporting units. The annual assessment performed in 2020 for one of the Company’s reporting units, Rebar Fabrication, used forward-looking projections in future cash flows. The fair value of this reporting unit exceeded its carrying value by approximately 99% in the most recent assessment. The reporting unit was profitable in 2020 and we expect it to be profitable in 2021. If our assessment of the relevant facts and circumstances changes, or the actual performance of this reporting unit falls short of expected results, non-cash impairment charges may be required. Total goodwill associated with the Rebar Fabrication reporting unit was $374.1 million as of July 3, 2021 ($364.3 million as of December 31, 2020). An impairment of goodwill may also lead us to record an impairment of other intangible assets. Total finite-lived intangible assets associated with the Rebar Fabrication reporting unit were $55.2 million as of July 3, 2021 ($58.8 million as of December 31, 2020). There have been no triggering events requiring an interim assessment for impairment of the Rebar Fabrication reporting unit since the most recent annual goodwill impairment testing date. The annual assessment performed in 2020 for one of the Company’s reporting units, Grating, used forward-looking projections and included continued positive future cash flows. The fair value of this reporting unit exceeded its carrying value by approximately 88% in the most recent assessment. If our assessment of the relevant facts and circumstances changes, or the actual performance of this reporting unit falls short of expected results, non-cash impairment charges may be required. Total goodwill associated with the Grating reporting unit was $37.4 million as of July 3, 2021 ($37.0 million as of December 31, 2020). Intangible assets with estimated useful lives of five to 22 years are amortized on a straight-line or accelerated basis and were comprised of the following as of July 3, 2021 and December 31, 2020 (in thousands): July 3, 2021 December 31, 2020 Gross Amount Accumulated Amortization Gross Amount Accumulated Amortization Customer relationships $ 1,422,758 $ 874,016 $ 1,421,962 $ 838,443 Trademarks and trade names 162,608 103,933 162,365 100,000 Other 63,821 44,037 63,822 41,685 $ 1,649,187 $ 1,021,986 $ 1,648,149 $ 980,128 Intangible asset amortization expense in the second quarter of 2021 and 2020 was $20.8 million and $20.7 million, respectively, and $41.9 million and $42.2 million in the first six months of 2021 and 2020, respectively. Annual amortization expense is estimated to be $82.7 million in 2021; $81.1 million in 2022; $80.4 million in 2023; $79.6 million in 2024; and $78.6 million in 2025.

Current Liabilities

Current Liabilities	6 Months Ended
	Jul. 03, 2021
Payables And Accruals [Abstract]
Current Liabilities	5. Current Liabilities Book overdrafts, included in accounts payable in the condensed consolidated balance sheets, were $181.1 million at July 3, 2021 ($210.5 million at December 31, 2020). Dividends payable, included in accrued expenses and other current liabilities in the condensed consolidated balance sheets, were $120.1 million at July 3, 2021 ($123.9 million at December 31, 2020).

Fair Value Measurements

Fair Value Measurements	6 Months Ended
	Jul. 03, 2021
Fair Value Disclosures [Abstract]
Fair Value Measurements	6. Fair Value Measurements The following table summarizes information regarding Nucor’s financial assets and financial liabilities that were measured at fair value as of July 3, 2021 and December 31, 2020 (in thousands). Nucor does not have any non-financial assets or non-financial liabilities that are measured at fair value on a recurring basis. Fair Value Measurements at Reporting Date Using Description Carrying Amount in Condensed Consolidated Balance Sheets Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) As of July 3, 2021 Assets: Cash equivalents $ 2,204,795 $ 2,204,795 $ - $ - Short-term investments 398,409 398,409 - - Restricted cash and cash equivalents 84,350 84,350 - - Derivative contracts 6,800 - 6,800 - Total assets $ 2,694,354 $ 2,687,554 $ 6,800 $ - Liabilities: Derivative contracts $ (4,730 ) $ - $ (4,730 ) $ - As of December 31, 2020 Assets: Cash equivalents $ 2,186,820 $ 2,186,820 $ - $ - Short-term investments 408,004 408,004 - - Restricted cash and cash equivalents 115,258 115,258 - - Total assets $ 2,710,082 $ 2,710,082 $ - $ - Liabilities: Derivative contracts $ (14,361 ) $ - $ (14,361 ) $ - Fair value measurements for Nucor’s cash equivalents, short-term investments and restricted cash and cash equivalents are classified under Level 1 because such measurements are based on quoted market prices in active markets for identical assets. Our short-term investments at July 3, 2021 consisted of certificates of deposit, commercial paper and corporate notes. Fair value measurements for Nucor’s derivatives are classified under Level 2 because such measurements are based on published market prices for similar assets or are estimated based on observable inputs such as interest rates, yield curves, credit risks, spot and future commodity prices, and spot and future exchange rates. There were no transfers between the levels in the fair value hierarchy for the periods presented. The fair value of short-term and long-term debt, including current maturities, was approximately $5.90 billion at July 3, 2021 ($6.05 billion at December 31, 2020). The debt fair value estimates are classified under Level 2 because such estimates are based on readily available market prices of our debt at July 3, 2021 and December 31, 2020, or similar debt with the same maturities, ratings and interest rates.

Contingencies

Contingencies	6 Months Ended
	Jul. 03, 2021
Commitments And Contingencies Disclosure [Abstract]
Contingencies	7. Contingencies Nucor is subject to environmental laws and regulations established by federal, state and local authorities and, accordingly, makes provisions for the estimated costs of compliance. Of the undiscounted total of $14.2 million of accrued environmental costs at July 3, 2021 ($16.0 million at December 31, 2020), $2.9 million was classified in accrued expenses and other current liabilities ($5.6 million at December 31, 2020) and $11.3 million was classified in deferred credits and other liabilities ($10.4 million at December 31, 2020). Inherent uncertainties exist in these estimates primarily due to unknown conditions, evolving remediation technology and changing governmental regulations, legal standards and enforcement priorities. We are from time to time a party to various lawsuits, claims and other legal proceedings that arise in the ordinary course of business. With respect to all such lawsuits, claims and proceedings, we record reserves when it is probable a liability has been incurred and the amount of loss can be reasonably estimated. We do not believe that any of these proceedings, individually or in the aggregate, would be expected to have a material adverse effect on our results of operations, financial position or cash flows. Nucor maintains liability insurance with self-insurance limits for certain risks.

Stock-Based Compensation

Stock-Based Compensation	6 Months Ended
	Jul. 03, 2021
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock-Based Compensation	8. Stock-Based Compensation Overview The Company maintains the Nucor Corporation 2014 Omnibus Incentive Compensation Plan (the “Omnibus Plan”) under which the Company may award stock-based compensation to key employees, officers and non-employee directors. The Company’s stockholders approved an amendment and restatement of the Omnibus Plan on May 14, 2020. The Omnibus Plan, as amended and restated, permits the award of stock options, restricted stock units, restricted shares and other stock-based awards for up to 19.0 million shares of the Company’s common stock. As of July 3, 2021, 7.0 million shares remained available for award under the Omnibus Plan. The Company also maintains a number of inactive plans under which stock-based awards remain outstanding but no further awards may be made. As of July 3, 2021, 0.5 million shares were reserved for issuance upon the future settlement of outstanding awards under such inactive plans. Stock Options Stock options may be granted to Nucor’s key employees, officers and non-employee directors with exercise prices at 100% of the market value on the date of the grant. The stock options granted are generally exercisable at the end of three years and have a term of 10 years. A summary of activity under Nucor’s stock option plans for the first six months of 2021 is as follows (shares in thousands): Weighted- Weighted- Average Average Aggregate Exercise Remaining Intrinsic Shares Price Contractual Life Value Number of shares under stock options: Outstanding at beginning of year 3,916 $ 50.03 Granted 138 $ 110.74 Exercised (2,554 ) $ 50.43 $ 49,707 Canceled - $ - Outstanding at July 3, 2021 1,500 $ 54.92 6.6 years $ 64,347 Stock options exercisable at July 3, 2021 837 $ 53.86 4.8 years $ 35,916 For the 2021 stock option grant, the grant date fair value of $32.30 per share was calculated using the Black-Scholes options pricing model with the following assumptions: Exercise price $ 110.74 Expected dividend yield 1.46 % Expected stock price volatility 32.86 % Risk-free interest rate 1.28 % Expected life (years) 6.5 Stock options granted to employees who are eligible for retirement on the date of the grant are expensed immediately since these awards vest upon retirement from the Company. Retirement, for purposes of vesting in these stock options, means termination of employment after satisfying age and years of service requirements. Similarly, stock options granted to employees who will become retirement-eligible prior to the end of the vesting term are expensed over the period through which the employee will become retirement-eligible. Compensation expense for stock options granted to employees who will not become retirement-eligible prior to the end of the vesting term is recognized on a straight-line basis over the vesting period. Compensation expense for stock options was $2.6 million and $1.8 million in the second quarter of 2021 and 2020, respectively, and $2.9 million and $2.1 million in the first six months of 2021 and 2020, respectively. As of July 3, 2021, unrecognized compensation expense related to stock options was $4.0 million, which is expected to be recognized over a weighted-average period of 2.4 years. Restricted Stock Units Nucor annually grants restricted stock units (“RSUs”) to key employees, officers and non-employee directors. The RSUs granted to key employees and officers vest and are converted to common stock in three equal installments on each of the first three anniversaries of the grant date. Retirement, for purposes of vesting in these RSUs only, means termination of employment with approval of the Compensation and Executive Development Committee of the Board of Directors after satisfying age and years of service requirements. RSUs granted to a non-employee director are fully vested on the grant date and are payable to the non-employee director in the form of common stock after the termination of the director’s service on the Board of Directors. RSUs granted to employees who are eligible for retirement on the date of the grant are expensed immediately, and RSUs granted to employees who will become retirement-eligible prior to the end of the vesting term are expensed over the period through which the employee will become retirement-eligible since these awards vest upon retirement from the Company. Compensation expense for RSUs granted to employees who will not become retirement-eligible prior to the end of the vesting term is recognized on a straight-line basis over the vesting period. Cash dividend equivalents are paid to holders of RSUs each quarter. Dividend equivalents paid on RSUs expected to vest are recognized as a reduction in retained earnings. The fair value of an RSU is determined based on the closing price of Nucor’s common stock on the date of the grant. A summary of Nucor’s RSU activity for the first six months of 2021 is as follows (shares in thousands): Shares Grant Date Fair Value Restricted stock units: Unvested at beginning of year 1,830 $ 47.33 Granted 397 $ 110.74 Vested (902 ) $ 57.40 Canceled (52 ) $ 47.62 Unvested at July 3, 2021 1,273 $ 59.97 Compensation expense for RSUs was $22.7 million and $26.8 million in the second quarter of 2021 and 2020, respectively, and $32.0 million and $36.8 million in the first six months of 2021 and 2020, respectively. As of July 3, 2021, unrecognized compensation expense related to unvested RSUs was $63.6 million, which is expected to be recognized over a weighted-average period of 1.5 years. Restricted Stock Awards Prior to their expiration effective December 31, 2017, the Nucor Corporation Senior Officers Long-Term Incentive Plan and the Nucor Corporation Senior Officers Annual Incentive Plan authorized the award of shares of common stock to officers subject to certain conditions and restrictions. Effective January 1, 2018, the Company adopted supplements to the Omnibus Plan with terms that permit the award of shares of common stock to officers subject to the conditions and restrictions described below, which are substantially similar to those of the expired Senior Officers Long-Term Incentive Plan and Senior Officers Annual Incentive Plan. The expired Senior Officers Long-Term Incentive Plan, together with the applicable supplement, is referred to below as the “LTIP,” and the expired Senior Officers Annual Incentive Plan, together with the applicable supplement, is referred to below as the “AIP.” The LTIP provides for the award of shares of restricted common stock at the end of each LTIP performance measurement period at no cost to officers if certain financial performance goals are met during the period. One-third of the LTIP restricted stock award vests upon each of the first three anniversaries of the award date or, if earlier, upon the officer’s attainment of age 55 while employed by Nucor. Although participants are entitled to cash dividends and may vote such awarded shares, the sale or transfer of such shares is limited during the restricted period. The AIP provides for the payment of annual cash incentive awards. An AIP participant may elect, however, to defer payment of up to one-half of an AIP award. In such event, the deferred AIP award is converted into common stock units and credited with a deferral incentive, in the form of additional common stock units, equal to 25% of the number of common stock units attributable to the deferred AIP award. Common stock units attributable to deferred AIP awards are fully vested. Common stock units credited as a deferral incentive vest upon the AIP participant’s attainment of age 55 while employed by Nucor. Vested common stock units are paid to AIP participants in the form of shares of common stock following their termination of employment with Nucor. A summary of Nucor’s restricted stock activity under the AIP and the LTIP for the first six months of 2021 is as follows (shares in thousands): Grant Date Shares Fair Value Restricted stock units and restricted stock awards: Unvested at beginning of year 127 $ 49.94 Granted 262 $ 65.61 Vested (240 ) $ 63.10 Canceled (9 ) $ 48.75 Unvested at July 3, 2021 140 $ 56.77 Compensation expense for common stock and common stock units awarded under the AIP and the LTIP is recorded over the performance measurement and vesting periods based on the anticipated number and market value of shares of common stock and common stock units to be awarded. Compensation expense for anticipated awards based upon Nucor’s financial performance, exclusive of amounts payable in cash, was $21.6 million and $2.8 million in the second quarter of 2021 and 2020, respectively, and $31.8 million and $2.5 million in the first six months of 2021 and 2020, respectively. As of July 3, 2021, unrecognized compensation expense related to unvested restricted stock awards was $2.1 million, which is expected to be recognized over a weighted-average period of 1.9 years.

Employee Benefit Plan

Employee Benefit Plan	6 Months Ended
	Jul. 03, 2021
Compensation And Retirement Disclosure [Abstract]
Employee Benefit Plan	9. Employee Benefit Plan Nucor makes contributions to a Profit Sharing and Retirement Savings Plan for qualified employees based on the profitability of the Company. Nucor’s expense for these benefits totaled $192.4 million and $20.4 million in the second quarter of 2021 and 2020, respectively, and $321.3 million and $32.0 million in the first six months of 2021 and 2020, respectively. The related liability for these benefits is included in salaries, wages and related accruals in the condensed consolidated balance sheets.

Interest Expense (Income)

Interest Expense (Income)	6 Months Ended
	Jul. 03, 2021
Banking And Thrift Interest [Abstract]
Interest Expense (Income)	10. Interest Expense (Income) The components of net interest expense for the second quarter and first six months of 2021 and 2020 are as follows (in thousands): Three Months (13 Weeks) Ended Six Months (26 Weeks) Ended July 3, 2021 July 4, 2020 July 3, 2021 July 4, 2020 Interest expense $ 37,661 $ 38,849 $ 78,631 $ 86,445 Interest income (1,881 ) (3,042 ) (3,207 ) (9,728 ) Interest expense, net $ 35,780 $ 35,807 $ 75,424 $ 76,717

Income Taxes

Income Taxes	6 Months Ended
	Jul. 03, 2021
Income Tax Disclosure [Abstract]
Income Taxes	11. Income Taxes The effective tax rate for the second quarter of 2021 was 22.4% compared to 26.5% for the second quarter of 2020. The effective tax rate for the second quarter of 2020 was elevated, relative to the second quarter of 2021, primarily due to a $5.3 million unfavorable non-cash, out-of-period adjustment to deferred tax balances. The out-of-period adjustment was not material to any previously reported period. Nucor has concluded U.S. federal income tax matters for tax years through 2014 and for tax year 2016. The tax years 2015 and 2017 through 2019 remain open to examination by the Internal Revenue Service. The 2015 Canadian income tax returns for Harris Steel Group Inc. and certain related affiliates are currently under examination by the Canada Revenue Agency. The tax years 2014 through 2020 remain open to examination by other major taxing jurisdictions to which Nucor is subject (primarily Canada and other state and local jurisdictions). Non-current deferred tax liabilities included in deferred credits and other liabilities in the condensed consolidated balance sheets were $701.9 million at July 3, 2021 ($596.4 million at December 31, 2020).

Stockholders' Equity

Stockholders' Equity	6 Months Ended
	Jul. 03, 2021
Equity [Abstract]
Stockholders' Equity	12. Stockholders’ Equity The following tables reflect the changes in stockholders’ equity attributable to both Nucor and the noncontrolling interests of Nucor’s joint ventures, primarily Nucor-Yamato Steel Company (Limited Partnership) (“NYS”) of which Nucor owns 51% Three Months (13 Weeks) Ended July 3, 2021 Accumulated Total Additional Other Treasury Stock Nucor Common Stock Paid-in Retained Comprehensive (at cost) Stockholders' Noncontrolling Total Shares Amount Capital Earnings Income (Loss) Shares Amount Equity Interests BALANCES, April 3, 2021 $ 11,861,723 380,154 $ 152,061 $ 2,160,909 $ 12,163,626 $ (103,560 ) 80,912 $ (2,925,796 ) $ 11,447,240 $ 414,483 Net earnings 1,571,459 - - - 1,506,868 - - - 1,506,868 64,591 Other comprehensive income (loss) 29,831 - - - - 29,831 - - 29,831 - Stock options exercised 21,276 - - 5,337 - - (419 ) 15,939 21,276 - Stock option expense 2,575 - - 2,575 - - - - 2,575 - Issuance of stock under award plans, net of forfeitures (18,338 ) - - (50,566 ) - - (799 ) 32,228 (18,338 ) - Amortization of unearned compensation (1,100 ) - - (1,100 ) - - - - (1,100 ) - Treasury stock acquired (614,286 ) - - - - - 6,765 (614,286 ) (614,286 ) - Cash dividends declared (120,088 ) - - - (120,088 ) - - - (120,088 ) - Distributions to noncontrolling interests (23,401 ) - - - - - - - - (23,401 ) BALANCES, July 3, 2021 $ 12,709,651 380,154 $ 152,061 $ 2,117,155 $ 13,550,406 $ (73,729 ) 86,459 $ (3,491,915 ) $ 12,253,978 $ 455,673 Six Months (26 Weeks) Ended July 3, 2021 Accumulated Total Additional Other Treasury Stock Nucor Common Stock Paid-in Retained Comprehensive (at cost) Stockholders' Noncontrolling Total Shares Amount Capital Earnings Income (Loss) Shares Amount Equity Interests BALANCES, December 31, 2020 $ 11,231,861 380,154 $ 152,061 $ 2,121,288 $ 11,343,852 $ (118,861 ) 77,909 $ (2,709,675 ) $ 10,788,665 $ 443,196 Net earnings 2,558,973 - - - 2,449,300 - - - 2,449,300 109,673 Other comprehensive income (loss) 45,132 - - - - 45,132 - - 45,132 - Stock options exercised 128,800 - - 35,825 - - (2,554 ) 92,975 128,800 - Stock option expense 2,908 - - 2,908 - - - - 2,908 - Issuance of stock under award plans, net of forfeitures (2,736 ) - - (43,666 ) - - (1,041 ) 40,930 (2,736 ) - Amortization of unearned compensation 800 - - 800 - - - - 800 - Treasury stock acquired (916,145 ) - - - - - 12,145 (916,145 ) (916,145 ) - Cash dividends declared (242,746 ) - - - (242,746 ) - - - (242,746 ) - Distributions to noncontrolling interests (97,196 ) - - - - - - - - (97,196 ) BALANCES, July 3, 2021 $ 12,709,651 380,154 $ 152,061 $ 2,117,155 $ 13,550,406 $ (73,729 ) 86,459 $ (3,491,915 ) $ 12,253,978 $ 455,673 Three Months (13 Weeks) Ended July 4, 2020 Accumulated Total Additional Other Treasury Stock Nucor Common Stock Paid-in Retained Comprehensive (at cost) Stockholders' Noncontrolling Total Shares Amount Capital Earnings Income (Loss) Shares Amount Equity Interests BALANCES, April 4, 2020 $ 10,596,069 380,154 $ 152,061 $ 2,119,370 $ 11,012,690 $ (367,627 ) 79,019 $ (2,748,290 ) $ 10,168,204 $ 427,865 Net earnings 133,153 - - - 108,881 - - - 108,881 24,272 Other comprehensive income (loss) 26,791 - - - - 26,791 - - 26,791 - Stock option expense 1,864 - - 1,864 - - - - 1,864 - Issuance of stock under award plans, net of forfeitures 11,618 - - (14,827 ) - - (760 ) 26,445 11,618 - Amortization of unearned compensation 500 - - 500 - - - - 500 - Cash dividends declared (123,038 ) - - - (123,038 ) - - - (123,038 ) - Distributions to noncontrolling interests (23,472 ) - - - - - - - - (23,472 ) BALANCES, July 4, 2020 $ 10,623,485 380,154 $ 152,061 $ 2,106,907 $ 10,998,533 $ (340,836 ) 78,259 $ (2,721,845 ) $ 10,194,820 $ 428,665 Six Months (26 Weeks) Ended July 4, 2020 Accumulated Total Additional Other Treasury Stock Nucor Common Stock Paid-in Retained Comprehensive (at cost) Stockholders' Noncontrolling Total Shares Amount Capital Earnings Income (Loss) Shares Amount Equity Interests BALANCES, December 31, 2019 $ 10,791,176 380,154 $ 152,061 $ 2,107,646 $ 11,115,056 $ (302,966 ) 78,342 $ (2,713,931 ) $ 10,357,866 $ 433,310 Net earnings 187,532 - - - 129,212 - - - 129,212 58,320 Other comprehensive income (loss) (37,870 ) - - - - (37,870 ) - - (37,870 ) - Stock option expense 2,139 - - 2,139 - - - - 2,139 - Issuance of stock under award plans, net of forfeitures 27,807 - - (3,778 ) - - (908 ) 31,585 27,807 - Amortization of unearned compensation 900 - - 900 - - - - 900 - Treasury stock acquired (39,499 ) - - - - - 825 (39,499 ) (39,499 ) - Cash dividends declared (245,735 ) - - - (245,735 ) - - - (245,735 ) - Distributions to noncontrolling interests (62,965 ) - - - - - - - - (62,965 ) BALANCES, July 4, 2020 $ 10,623,485 380,154 $ 152,061 $ 2,106,907 $ 10,998,533 $ (340,836 ) 78,259 $ (2,721,845 ) $ 10,194,820 $ 428,665 Dividends declared per share were $0.405 per share in the second quarter of 2021 ($0.4025 per share in the second quarter of 2020) and $0.81 per share in the first six months of 2021 ($0.805 per share in the first six months of 2020). On May 13, 2021, the Company announced that the Board of Directors had approved a new share repurchase program under which the Company is authorized to repurchase up to $3.00 billion of the Company’s common stock and terminated any previously authorized share repurchase programs. Share repurchases will be made from time to time in the open market at prevailing market prices or through private transactions or block trades. The timing and amount of repurchases will depend on market conditions, share price, applicable legal requirements and other factors. The share repurchase authorization is discretionary and has no expiration date. As of July 3, 2021, the Company had approximately $2.80 billion remaining available for share repurchases under its newly authorized program.

Accumulated Other Comprehensive

Accumulated Other Comprehensive Income (Loss)	6 Months Ended
	Jul. 03, 2021
Equity [Abstract]
Accumulated Other Comprehensive Income (Loss)	13. Accumulated Other Comprehensive Income (Loss) The following tables reflect the changes in accumulated other comprehensive income (loss) by component for the three months and six months ended July 3, 2021 and July 4, 2020 (in thousands): Three-Month (13-Week) Period Ended July 3, 2021 Gains and Losses on Foreign Currency Adjustment to Early Hedging Derivatives Gain (Loss) Retiree Medical Plan Total Accumulated other comprehensive income (loss) at April 3, 2021 $ (3,200 ) $ (107,026 ) $ 6,666 $ (103,560 ) Other comprehensive income (loss) before reclassifications 8,204 21,431 - 29,635 Amounts reclassified from accumulated other comprehensive income (loss) into earnings (1) 196 - - 196 Net current-period other comprehensive income (loss) 8,400 21,431 - 29,831 Accumulated other comprehensive income (loss) at July 3, 2021 $ 5,200 $ (85,595 ) $ 6,666 $ (73,729 ) Six-Month (26-Week) Period Ended July 3, 2021 Gains and Losses on Foreign Currency Adjustment to Early Hedging Derivatives Gain (Loss) Retiree Medical Plan Total Accumulated other comprehensive income (loss) at December 31, 2020 $ (4,700 ) $ (120,827 ) $ 6,666 $ (118,861 ) Other comprehensive income (loss) before reclassifications 9,203 35,232 - 44,435 Amounts reclassified from accumulated other comprehensive income (loss) into earnings (1) 697 - - 697 Net current-period other comprehensive income (loss) 9,900 35,232 - 45,132 Accumulated other comprehensive income (loss) at July 3, 2021 $ 5,200 $ (85,595 ) $ 6,666 $ (73,729 ) (1) Includes $196 and $697 of accumulated other comprehensive income (loss) reclassifications into cost of products sold for net losses on commodity contracts in the second quarter and first six months of 2021, respectively. The tax impact of those reclassifications was $0 and $100 in the second quarter and first six months of 2021, respectively. Three-Month (13-Week) Period Ended July 4, 2020 Gains and Losses on Foreign Currency Adjustment to Early Hedging Derivatives Gain (Loss) Retiree Medical Plan Total Accumulated other comprehensive income (loss) at April 4, 2020 $ (14,200 ) $ (361,234 ) $ 7,807 $ (367,627 ) Other comprehensive income (loss) before reclassifications 757 23,491 - 24,248 Amounts reclassified from accumulated other comprehensive income (loss) into earnings ( 2 ) 2,543 - - 2,543 Net current-period other comprehensive income (loss) 3,300 23,491 - 26,791 Accumulated other comprehensive income (loss) at July 4, 2020 $ (10,900 ) $ (337,743 ) $ 7,807 $ (340,836 ) Six-Month (26-Week) Period Ended July 4, 2020 Gains and Losses on Foreign Currency Adjustment to Early Hedging Derivatives Gain (Loss) Retiree Medical Plan Total Accumulated other comprehensive income (loss) at December 31, 2019 $ (14,000 ) $ (296,773 ) $ 7,807 $ (302,966 ) Other comprehensive income (loss) before reclassifications (1,499 ) (40,970 ) - (42,469 ) Amounts reclassified from accumulated other comprehensive income (loss) into earnings (2) 4,599 - - 4,599 Net current-period other comprehensive income (loss) 3,100 (40,970 ) - (37,870 ) Accumulated other comprehensive income (loss) at July 4, 2020 $ (10,900 ) $ (337,743 ) $ 7,807 $ (340,836 ) (2) Includes $2,543 and $4,599 of accumulated other comprehensive income (loss) reclassifications into cost of products sold for net losses on commodity contracts in the second quarter and first six months of 2020, respectively. The tax impact of those reclassifications was $900 and $1,600 in the second quarter and first six months of 2020, respectively.

Segments

Segments	6 Months Ended
	Jul. 03, 2021
Segment Reporting [Abstract]
Segments	14. Segments Nucor reports its results in the following segments: steel mills, steel products and raw materials. The steel mills segment includes carbon and alloy steel in sheet, bars, structural and plate; steel trading businesses; rebar distribution businesses; and Nucor’s equity method investments in NuMit LLC (“NuMit”) and Nucor-JFE Steel Mexico, S. de R.L. de C.V. (“Nucor-JFE”). The steel products segment includes steel joists and joist girders, steel deck, fabricated concrete reinforcing steel, cold finished steel, precision castings, steel fasteners, metal building systems, steel grating, tubular products businesses, piling products business, and wire and wire mesh. The raw materials segment includes The David J. Joseph Company and its affiliates (“DJJ”), primarily a scrap broker and processor; Nu-Iron Unlimited and Nucor Steel Louisiana LLC (“Nucor Steel Louisiana”), two facilities that produce direct reduced iron (“DRI”) used by the steel mills; and our natural gas production operations. Net interest expense on long-term debt, charges and credits associated with changes in allowances to eliminate intercompany profit in inventory, profit sharing expense and stock-based compensation are shown under Corporate/eliminations. Corporate assets primarily include cash and cash equivalents, short-term investments, restricted cash and cash equivalents, allowances to eliminate intercompany profit in inventory, deferred income tax assets, federal and state income taxes receivable and investments in and advances to affiliates. Nucor’s results by segment for the second quarter and first six months of 2021 and 2020 were as follows (in thousands): Three Months (13 Weeks) Ended Six Months (26 Weeks) Ended July 3, 2021 July 4, 2020 July 3, 2021 July 4, 2020 Net sales to external customers: Steel mills $ 5,909,909 $ 2,513,961 $ 10,518,686 $ 6,033,231 Steel products 2,241,107 1,523,168 4,051,162 3,250,022 Raw materials 638,148 290,177 1,236,456 668,390 $ 8,789,164 $ 4,327,306 $ 15,806,304 $ 9,951,643 Intercompany sales: Steel mills $ 1,496,298 $ 663,244 $ 2,721,411 $ 1,532,336 Steel products 80,394 63,205 151,613 146,574 Raw materials 4,009,808 1,484,982 7,656,003 3,908,787 Corporate/eliminations (5,586,500 ) (2,211,431 ) (10,529,027 ) (5,587,697 ) $ - $ - $ - $ - Earnings (loss) before income taxes and noncontrolling interests: Steel mills $ 2,174,807 $ 150,424 $ 3,489,781 $ 306,930 Steel products 259,330 152,874 471,142 315,433 Raw materials 120,143 (1,389 ) 343,378 (9,300 ) Corporate/eliminations (528,532 ) (120,852 ) (980,307 ) (285,709 ) $ 2,025,748 $ 181,057 $ 3,323,994 $ 327,354 July 3, 2021 Dec. 31, 2020 Segment assets: Steel mills $ 11,734,231 $ 9,708,260 Steel products 5,342,505 4,461,042 Raw materials 3,876,540 3,324,489 Corporate/eliminations 2,042,306 2,631,603 $ 22,995,582 $ 20,125,394

Revenue

Revenue	6 Months Ended
	Jul. 03, 2021
Revenue From Contract With Customer [Abstract]
Revenue	15. Revenue The following tables disaggregate our revenue by major source for the second quarter and first six months of 2021 and 2020 (in thousands): Three Months (13 Weeks) Ended July 3, 2021 Six Months (26 Weeks) Ended July 3, 2021 Steel Mills Steel Products Raw Materials Total Steel Mills Steel Products Raw Materials Total Sheet $ 3,104,304 $ - $ - $ 3,104,304 $ 5,455,759 $ - $ - $ 5,455,759 Bar 1,515,115 - - 1,515,115 2,776,157 - - 2,776,157 Structural 619,541 - - 619,541 1,096,736 - - 1,096,736 Plate 670,949 - - 670,949 1,190,034 - - 1,190,034 Tubular Products - 512,503 - 512,503 - 887,156 - 887,156 Rebar Fabrication - 480,727 - 480,727 - 867,284 - 867,284 Other Steel Products - 1,247,877 - 1,247,877 - 2,296,722 - 2,296,722 Raw Materials - - 638,148 638,148 - - 1,236,456 1,236,456 $ 5,909,909 $ 2,241,107 $ 638,148 $ 8,789,164 $ 10,518,686 $ 4,051,162 $ 1,236,456 $ 15,806,304 Three Months (13 Weeks) Ended July 4, 2020 Six Months (26 Weeks) Ended July 4, 2020 Steel Mills Steel Products Raw Materials Total Steel Mills Steel Products Raw Materials Total Sheet $ 1,065,004 $ - $ - $ 1,065,004 $ 2,643,433 $ - $ - $ 2,643,433 Bar 811,054 - - 811,054 1,873,720 - - 1,873,720 Structural 347,258 - - 347,258 797,757 - - 797,757 Plate 290,645 - - 290,645 718,321 - - 718,321 Tubular Products - 250,311 - 250,311 - 555,368 - 555,368 Rebar Fabrication - 413,916 - 413,916 - 837,232 - 837,232 Other Steel Products - 858,941 - 858,941 - 1,857,422 - 1,857,422 Raw Materials - - 290,177 290,177 - - 668,390 668,390 $ 2,513,961 $ 1,523,168 $ 290,177 $ 4,327,306 $ 6,033,231 $ 3,250,022 $ 668,390 $ 9,951,643 Contract liabilities are primarily related to deferred revenue resulting from cash payments received in advance from customers to protect against credit risk. Contract liabilities totaled $159.2 million as of July 3, 2021 ($120.2 million as of December 31, 2020), and are included in accrued expenses and other current liabilities in the condensed consolidated balance sheets.

Earnings Per Share

Earnings Per Share	6 Months Ended
	Jul. 03, 2021
Earnings Per Share [Abstract]
Earnings Per Share	16. Earnings Per Share The computations of basic and diluted net earnings per share for the second quarter and first six months of 2021 and 2020 are as follows (in thousands, except per share amounts): Three Months (13 Weeks) Ended Six Months (26 Weeks) Ended July 3, 2021 July 4, 2020 July 3, 2021 July 4, 2020 Basic net earnings per share: Basic net earnings $ 1,506,868 $ 108,881 $ 2,449,300 $ 129,212 Earnings allocated to participating securities (6,676 ) (792 ) (12,426 ) (1,423 ) Net earnings available to common stockholders $ 1,500,192 $ 108,089 $ 2,436,874 $ 127,789 Basic average shares outstanding 296,817 302,921 299,359 302,915 Basic net earnings per share $ 5.05 $ 0.36 $ 8.14 $ 0.42 Diluted net earnings per share: Diluted net earnings $ 1,506,868 $ 108,881 $ 2,449,300 $ 129,212 Earnings allocated to participating securities (6,649 ) (792 ) (12,385 ) (1,423 ) Net earnings available to common stockholders $ 1,500,219 $ 108,089 $ 2,436,915 $ 127,789 Diluted average shares outstanding: Basic average shares outstanding 296,817 302,921 299,359 302,915 Dilutive effect of stock options and other 712 12 379 17 297,529 302,933 299,738 302,932 Diluted net earnings per share $ 5.04 $ 0.36 $ 8.13 $ 0.42 The following stock options were excluded from the computation of diluted net earnings per share for the second quarter and first six months of 2021 and 2020 because their effect would have been anti-dilutive (shares in thousands): Three Months (13 Weeks) Ended Six Months (26 Weeks) Ended July 3, 2021 July 4, 2020 July 3, 2021 July 4, 2020 Anti-dilutive stock options: Weighted-average shares 52 3,749 152 3,724 Weighted-average exercise price $ 110.74 $ 50.69 $ 73.47 $ 51.04

Subsequent Events

Subsequent Events	6 Months Ended
	Jul. 03, 2021
Subsequent Events [Abstract]
Subsequent Events	17. Subsequent Events On August 9, 2021, Nucor acquired Cornerstone Building Brands, Inc.’s insulated metal panels (“IMP”) business for a cash purchase price of approximately $1 billion, subject to customary adjustments. The Company believes this acquisition is strategically important and will broaden value-added solutions Nucor is able to provide to targeted end markets as the use of IMP products reduce energy usage and overall operations-related greenhouse gas emissions. The IMP business Nucor is acquiring has seven manufacturing facilities located throughout North America. These locations will complement the footprint of Nucor Buildings as well as the Company’s existing IMP business, Truecore. On July 20, 2021, Nucor announced it had entered into an agreement to purchase Hannibal Industries, Inc. for a cash purchase price of approximately $370 million. Hannibal Industries is a leading national provider of steel racking solutions to warehouses and serves the e-commerce, industrial, food storage and retail segments. Hannibal Industries has manufacturing facilities in Los Angeles and Houston, as well as three distribution centers. The Company believes this acquisition is strategically important as it further deepens our ability to serve warehouse and distribution customers. We expect this transaction to close in August of 2021. On August 4, 2021, Nucor became an obligor with respect to $197.0 million in 40-year variable-rate Green Bonds to partially fund the capital costs, in particular the expenditures associated with pollution prevention and control (including waste recycling and waste reduction), of the construction of Nucor’s plate mill located in Brandenburg, Kentucky. The net proceeds from the debt issuance are being held in a trust account pending disbursement for the construction of the facility and will be accounted for as restricted cash. Funds will be disbursed from the trust account as qualified expenditures for the construction of the Brandenburg facility are made.

Goodwill and Other Intangible_2

Goodwill and Other Intangible Assets (Tables)	6 Months Ended
	Jul. 03, 2021
Goodwill And Intangible Assets Disclosure [Abstract]
Schedule of Change in Net Carrying Amount of Goodwill by Segment	The change in the net carrying amount of goodwill for the six months ended July 3, 2021 by segment was as follows (in thousands): Steel Mills Steel Products Raw Materials Total Balance at December 31, 2020 $ 612,470 $ 887,625 $ 729,577 $ 2,229,672 Acquisitions 705 - - 705 Other - (129 ) - (129 ) Translation - 11,310 - 11,310 Balance at July 3, 2021 $ 613,175 $ 898,806 $ 729,577 $ 2,241,558
Schedule of Intangible Assets	Intangible assets with estimated useful lives of five to 22 years are amortized on a straight-line or accelerated basis and were comprised of the following as of July 3, 2021 and December 31, 2020 (in thousands): July 3, 2021 December 31, 2020 Gross Amount Accumulated Amortization Gross Amount Accumulated Amortization Customer relationships $ 1,422,758 $ 874,016 $ 1,421,962 $ 838,443 Trademarks and trade names 162,608 103,933 162,365 100,000 Other 63,821 44,037 63,822 41,685 $ 1,649,187 $ 1,021,986 $ 1,648,149 $ 980,128

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	6 Months Ended
	Jul. 03, 2021
Fair Value Disclosures [Abstract]
Schedule of Financial Assets and Liabilities Measured at Fair Value	The following table summarizes information regarding Nucor’s financial assets and financial liabilities that were measured at fair value as of July 3, 2021 and December 31, 2020 (in thousands). Nucor does not have any non-financial assets or non-financial liabilities that are measured at fair value on a recurring basis. Fair Value Measurements at Reporting Date Using Description Carrying Amount in Condensed Consolidated Balance Sheets Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) As of July 3, 2021 Assets: Cash equivalents $ 2,204,795 $ 2,204,795 $ - $ - Short-term investments 398,409 398,409 - - Restricted cash and cash equivalents 84,350 84,350 - - Derivative contracts 6,800 - 6,800 - Total assets $ 2,694,354 $ 2,687,554 $ 6,800 $ - Liabilities: Derivative contracts $ (4,730 ) $ - $ (4,730 ) $ - As of December 31, 2020 Assets: Cash equivalents $ 2,186,820 $ 2,186,820 $ - $ - Short-term investments 408,004 408,004 - - Restricted cash and cash equivalents 115,258 115,258 - - Total assets $ 2,710,082 $ 2,710,082 $ - $ - Liabilities: Derivative contracts $ (14,361 ) $ - $ (14,361 ) $ -

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	6 Months Ended
	Jul. 03, 2021
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Summary of Stock Option Plans Activity	A summary of activity under Nucor’s stock option plans for the first six months of 2021 is as follows (shares in thousands): Weighted- Weighted- Average Average Aggregate Exercise Remaining Intrinsic Shares Price Contractual Life Value Number of shares under stock options: Outstanding at beginning of year 3,916 $ 50.03 Granted 138 $ 110.74 Exercised (2,554 ) $ 50.43 $ 49,707 Canceled - $ - Outstanding at July 3, 2021 1,500 $ 54.92 6.6 years $ 64,347 Stock options exercisable at July 3, 2021 837 $ 53.86 4.8 years $ 35,916
Schedule of Grant Date Fair Value Black-Scholes Option-Pricing Model Assumptions	For the 2021 stock option grant, the grant date fair value of $32.30 per share was calculated using the Black-Scholes options pricing model with the following assumptions: Exercise price $ 110.74 Expected dividend yield 1.46 % Expected stock price volatility 32.86 % Risk-free interest rate 1.28 % Expected life (years) 6.5
Summary of Nucor's RSU Activity	A summary of Nucor’s RSU activity for the first six months of 2021 is as follows (shares in thousands): Shares Grant Date Fair Value Restricted stock units: Unvested at beginning of year 1,830 $ 47.33 Granted 397 $ 110.74 Vested (902 ) $ 57.40 Canceled (52 ) $ 47.62 Unvested at July 3, 2021 1,273 $ 59.97
Summary of Nucor's Restricted Stock Activity under AIP and LTIP	A summary of Nucor’s restricted stock activity under the AIP and the LTIP for the first six months of 2021 is as follows (shares in thousands): Grant Date Shares Fair Value Restricted stock units and restricted stock awards: Unvested at beginning of year 127 $ 49.94 Granted 262 $ 65.61 Vested (240 ) $ 63.10 Canceled (9 ) $ 48.75 Unvested at July 3, 2021 140 $ 56.77

Interest Expense (Income) (Tabl

Interest Expense (Income) (Tables)	6 Months Ended
	Jul. 03, 2021
Banking And Thrift Interest [Abstract]
Schedule of Components of Net Interest Expense	The components of net interest expense for the second quarter and first six months of 2021 and 2020 are as follows (in thousands): Three Months (13 Weeks) Ended Six Months (26 Weeks) Ended July 3, 2021 July 4, 2020 July 3, 2021 July 4, 2020 Interest expense $ 37,661 $ 38,849 $ 78,631 $ 86,445 Interest income (1,881 ) (3,042 ) (3,207 ) (9,728 ) Interest expense, net $ 35,780 $ 35,807 $ 75,424 $ 76,717

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	6 Months Ended
	Jul. 03, 2021
Equity [Abstract]
Schedule of Changes in Stockholders' Equity	The following tables reflect the changes in stockholders’ equity attributable to both Nucor and the noncontrolling interests of Nucor’s joint ventures, primarily Nucor-Yamato Steel Company (Limited Partnership) (“NYS”) of which Nucor owns 51% Three Months (13 Weeks) Ended July 3, 2021 Accumulated Total Additional Other Treasury Stock Nucor Common Stock Paid-in Retained Comprehensive (at cost) Stockholders' Noncontrolling Total Shares Amount Capital Earnings Income (Loss) Shares Amount Equity Interests BALANCES, April 3, 2021 $ 11,861,723 380,154 $ 152,061 $ 2,160,909 $ 12,163,626 $ (103,560 ) 80,912 $ (2,925,796 ) $ 11,447,240 $ 414,483 Net earnings 1,571,459 - - - 1,506,868 - - - 1,506,868 64,591 Other comprehensive income (loss) 29,831 - - - - 29,831 - - 29,831 - Stock options exercised 21,276 - - 5,337 - - (419 ) 15,939 21,276 - Stock option expense 2,575 - - 2,575 - - - - 2,575 - Issuance of stock under award plans, net of forfeitures (18,338 ) - - (50,566 ) - - (799 ) 32,228 (18,338 ) - Amortization of unearned compensation (1,100 ) - - (1,100 ) - - - - (1,100 ) - Treasury stock acquired (614,286 ) - - - - - 6,765 (614,286 ) (614,286 ) - Cash dividends declared (120,088 ) - - - (120,088 ) - - - (120,088 ) - Distributions to noncontrolling interests (23,401 ) - - - - - - - - (23,401 ) BALANCES, July 3, 2021 $ 12,709,651 380,154 $ 152,061 $ 2,117,155 $ 13,550,406 $ (73,729 ) 86,459 $ (3,491,915 ) $ 12,253,978 $ 455,673 Six Months (26 Weeks) Ended July 3, 2021 Accumulated Total Additional Other Treasury Stock Nucor Common Stock Paid-in Retained Comprehensive (at cost) Stockholders' Noncontrolling Total Shares Amount Capital Earnings Income (Loss) Shares Amount Equity Interests BALANCES, December 31, 2020 $ 11,231,861 380,154 $ 152,061 $ 2,121,288 $ 11,343,852 $ (118,861 ) 77,909 $ (2,709,675 ) $ 10,788,665 $ 443,196 Net earnings 2,558,973 - - - 2,449,300 - - - 2,449,300 109,673 Other comprehensive income (loss) 45,132 - - - - 45,132 - - 45,132 - Stock options exercised 128,800 - - 35,825 - - (2,554 ) 92,975 128,800 - Stock option expense 2,908 - - 2,908 - - - - 2,908 - Issuance of stock under award plans, net of forfeitures (2,736 ) - - (43,666 ) - - (1,041 ) 40,930 (2,736 ) - Amortization of unearned compensation 800 - - 800 - - - - 800 - Treasury stock acquired (916,145 ) - - - - - 12,145 (916,145 ) (916,145 ) - Cash dividends declared (242,746 ) - - - (242,746 ) - - - (242,746 ) - Distributions to noncontrolling interests (97,196 ) - - - - - - - - (97,196 ) BALANCES, July 3, 2021 $ 12,709,651 380,154 $ 152,061 $ 2,117,155 $ 13,550,406 $ (73,729 ) 86,459 $ (3,491,915 ) $ 12,253,978 $ 455,673 Three Months (13 Weeks) Ended July 4, 2020 Accumulated Total Additional Other Treasury Stock Nucor Common Stock Paid-in Retained Comprehensive (at cost) Stockholders' Noncontrolling Total Shares Amount Capital Earnings Income (Loss) Shares Amount Equity Interests BALANCES, April 4, 2020 $ 10,596,069 380,154 $ 152,061 $ 2,119,370 $ 11,012,690 $ (367,627 ) 79,019 $ (2,748,290 ) $ 10,168,204 $ 427,865 Net earnings 133,153 - - - 108,881 - - - 108,881 24,272 Other comprehensive income (loss) 26,791 - - - - 26,791 - - 26,791 - Stock option expense 1,864 - - 1,864 - - - - 1,864 - Issuance of stock under award plans, net of forfeitures 11,618 - - (14,827 ) - - (760 ) 26,445 11,618 - Amortization of unearned compensation 500 - - 500 - - - - 500 - Cash dividends declared (123,038 ) - - - (123,038 ) - - - (123,038 ) - Distributions to noncontrolling interests (23,472 ) - - - - - - - - (23,472 ) BALANCES, July 4, 2020 $ 10,623,485 380,154 $ 152,061 $ 2,106,907 $ 10,998,533 $ (340,836 ) 78,259 $ (2,721,845 ) $ 10,194,820 $ 428,665 Six Months (26 Weeks) Ended July 4, 2020 Accumulated Total Additional Other Treasury Stock Nucor Common Stock Paid-in Retained Comprehensive (at cost) Stockholders' Noncontrolling Total Shares Amount Capital Earnings Income (Loss) Shares Amount Equity Interests BALANCES, December 31, 2019 $ 10,791,176 380,154 $ 152,061 $ 2,107,646 $ 11,115,056 $ (302,966 ) 78,342 $ (2,713,931 ) $ 10,357,866 $ 433,310 Net earnings 187,532 - - - 129,212 - - - 129,212 58,320 Other comprehensive income (loss) (37,870 ) - - - - (37,870 ) - - (37,870 ) - Stock option expense 2,139 - - 2,139 - - - - 2,139 - Issuance of stock under award plans, net of forfeitures 27,807 - - (3,778 ) - - (908 ) 31,585 27,807 - Amortization of unearned compensation 900 - - 900 - - - - 900 - Treasury stock acquired (39,499 ) - - - - - 825 (39,499 ) (39,499 ) - Cash dividends declared (245,735 ) - - - (245,735 ) - - - (245,735 ) - Distributions to noncontrolling interests (62,965 ) - - - - - - - - (62,965 ) BALANCES, July 4, 2020 $ 10,623,485 380,154 $ 152,061 $ 2,106,907 $ 10,998,533 $ (340,836 ) 78,259 $ (2,721,845 ) $ 10,194,820 $ 428,665

Accumulated Other Comprehensi_2

Accumulated Other Comprehensive Income (Loss) (Tables)	6 Months Ended
	Jul. 03, 2021
Equity [Abstract]
Components of Accumulated Other Comprehensive Income (Loss)	The following tables reflect the changes in accumulated other comprehensive income (loss) by component for the three months and six months ended July 3, 2021 and July 4, 2020 (in thousands): Three-Month (13-Week) Period Ended July 3, 2021 Gains and Losses on Foreign Currency Adjustment to Early Hedging Derivatives Gain (Loss) Retiree Medical Plan Total Accumulated other comprehensive income (loss) at April 3, 2021 $ (3,200 ) $ (107,026 ) $ 6,666 $ (103,560 ) Other comprehensive income (loss) before reclassifications 8,204 21,431 - 29,635 Amounts reclassified from accumulated other comprehensive income (loss) into earnings (1) 196 - - 196 Net current-period other comprehensive income (loss) 8,400 21,431 - 29,831 Accumulated other comprehensive income (loss) at July 3, 2021 $ 5,200 $ (85,595 ) $ 6,666 $ (73,729 ) Six-Month (26-Week) Period Ended July 3, 2021 Gains and Losses on Foreign Currency Adjustment to Early Hedging Derivatives Gain (Loss) Retiree Medical Plan Total Accumulated other comprehensive income (loss) at December 31, 2020 $ (4,700 ) $ (120,827 ) $ 6,666 $ (118,861 ) Other comprehensive income (loss) before reclassifications 9,203 35,232 - 44,435 Amounts reclassified from accumulated other comprehensive income (loss) into earnings (1) 697 - - 697 Net current-period other comprehensive income (loss) 9,900 35,232 - 45,132 Accumulated other comprehensive income (loss) at July 3, 2021 $ 5,200 $ (85,595 ) $ 6,666 $ (73,729 ) (1) Includes $196 and $697 of accumulated other comprehensive income (loss) reclassifications into cost of products sold for net losses on commodity contracts in the second quarter and first six months of 2021, respectively. The tax impact of those reclassifications was $0 and $100 in the second quarter and first six months of 2021, respectively. Three-Month (13-Week) Period Ended July 4, 2020 Gains and Losses on Foreign Currency Adjustment to Early Hedging Derivatives Gain (Loss) Retiree Medical Plan Total Accumulated other comprehensive income (loss) at April 4, 2020 $ (14,200 ) $ (361,234 ) $ 7,807 $ (367,627 ) Other comprehensive income (loss) before reclassifications 757 23,491 - 24,248 Amounts reclassified from accumulated other comprehensive income (loss) into earnings ( 2 ) 2,543 - - 2,543 Net current-period other comprehensive income (loss) 3,300 23,491 - 26,791 Accumulated other comprehensive income (loss) at July 4, 2020 $ (10,900 ) $ (337,743 ) $ 7,807 $ (340,836 ) Six-Month (26-Week) Period Ended July 4, 2020 Gains and Losses on Foreign Currency Adjustment to Early Hedging Derivatives Gain (Loss) Retiree Medical Plan Total Accumulated other comprehensive income (loss) at December 31, 2019 $ (14,000 ) $ (296,773 ) $ 7,807 $ (302,966 ) Other comprehensive income (loss) before reclassifications (1,499 ) (40,970 ) - (42,469 ) Amounts reclassified from accumulated other comprehensive income (loss) into earnings (2) 4,599 - - 4,599 Net current-period other comprehensive income (loss) 3,100 (40,970 ) - (37,870 ) Accumulated other comprehensive income (loss) at July 4, 2020 $ (10,900 ) $ (337,743 ) $ 7,807 $ (340,836 ) (2) Includes $2,543 and $4,599 of accumulated other comprehensive income (loss) reclassifications into cost of products sold for net losses on commodity contracts in the second quarter and first six months of 2020, respectively. The tax impact of those reclassifications was $900 and $1,600 in the second quarter and first six months of 2020, respectively.

Segments (Tables)

Segments (Tables)	6 Months Ended
	Jul. 03, 2021
Segment Reporting [Abstract]
Segments	Nucor’s results by segment for the second quarter and first six months of 2021 and 2020 were as follows (in thousands): Three Months (13 Weeks) Ended Six Months (26 Weeks) Ended July 3, 2021 July 4, 2020 July 3, 2021 July 4, 2020 Net sales to external customers: Steel mills $ 5,909,909 $ 2,513,961 $ 10,518,686 $ 6,033,231 Steel products 2,241,107 1,523,168 4,051,162 3,250,022 Raw materials 638,148 290,177 1,236,456 668,390 $ 8,789,164 $ 4,327,306 $ 15,806,304 $ 9,951,643 Intercompany sales: Steel mills $ 1,496,298 $ 663,244 $ 2,721,411 $ 1,532,336 Steel products 80,394 63,205 151,613 146,574 Raw materials 4,009,808 1,484,982 7,656,003 3,908,787 Corporate/eliminations (5,586,500 ) (2,211,431 ) (10,529,027 ) (5,587,697 ) $ - $ - $ - $ - Earnings (loss) before income taxes and noncontrolling interests: Steel mills $ 2,174,807 $ 150,424 $ 3,489,781 $ 306,930 Steel products 259,330 152,874 471,142 315,433 Raw materials 120,143 (1,389 ) 343,378 (9,300 ) Corporate/eliminations (528,532 ) (120,852 ) (980,307 ) (285,709 ) $ 2,025,748 $ 181,057 $ 3,323,994 $ 327,354 July 3, 2021 Dec. 31, 2020 Segment assets: Steel mills $ 11,734,231 $ 9,708,260 Steel products 5,342,505 4,461,042 Raw materials 3,876,540 3,324,489 Corporate/eliminations 2,042,306 2,631,603 $ 22,995,582 $ 20,125,394

Revenue (Tables)

Revenue (Tables)	6 Months Ended
	Jul. 03, 2021
Revenue From Contract With Customer [Abstract]
Schedule of Net Sales Disaggregates by Major Source	The following tables disaggregate our revenue by major source for the second quarter and first six months of 2021 and 2020 (in thousands): Three Months (13 Weeks) Ended July 3, 2021 Six Months (26 Weeks) Ended July 3, 2021 Steel Mills Steel Products Raw Materials Total Steel Mills Steel Products Raw Materials Total Sheet $ 3,104,304 $ - $ - $ 3,104,304 $ 5,455,759 $ - $ - $ 5,455,759 Bar 1,515,115 - - 1,515,115 2,776,157 - - 2,776,157 Structural 619,541 - - 619,541 1,096,736 - - 1,096,736 Plate 670,949 - - 670,949 1,190,034 - - 1,190,034 Tubular Products - 512,503 - 512,503 - 887,156 - 887,156 Rebar Fabrication - 480,727 - 480,727 - 867,284 - 867,284 Other Steel Products - 1,247,877 - 1,247,877 - 2,296,722 - 2,296,722 Raw Materials - - 638,148 638,148 - - 1,236,456 1,236,456 $ 5,909,909 $ 2,241,107 $ 638,148 $ 8,789,164 $ 10,518,686 $ 4,051,162 $ 1,236,456 $ 15,806,304 Three Months (13 Weeks) Ended July 4, 2020 Six Months (26 Weeks) Ended July 4, 2020 Steel Mills Steel Products Raw Materials Total Steel Mills Steel Products Raw Materials Total Sheet $ 1,065,004 $ - $ - $ 1,065,004 $ 2,643,433 $ - $ - $ 2,643,433 Bar 811,054 - - 811,054 1,873,720 - - 1,873,720 Structural 347,258 - - 347,258 797,757 - - 797,757 Plate 290,645 - - 290,645 718,321 - - 718,321 Tubular Products - 250,311 - 250,311 - 555,368 - 555,368 Rebar Fabrication - 413,916 - 413,916 - 837,232 - 837,232 Other Steel Products - 858,941 - 858,941 - 1,857,422 - 1,857,422 Raw Materials - - 290,177 290,177 - - 668,390 668,390 $ 2,513,961 $ 1,523,168 $ 290,177 $ 4,327,306 $ 6,033,231 $ 3,250,022 $ 668,390 $ 9,951,643

Earnings Per Share (Tables)

Earnings Per Share (Tables)	6 Months Ended
	Jul. 03, 2021
Earnings Per Share [Abstract]
Computations of Basic and Diluted Net Earnings Per Share	The computations of basic and diluted net earnings per share for the second quarter and first six months of 2021 and 2020 are as follows (in thousands, except per share amounts): Three Months (13 Weeks) Ended Six Months (26 Weeks) Ended July 3, 2021 July 4, 2020 July 3, 2021 July 4, 2020 Basic net earnings per share: Basic net earnings $ 1,506,868 $ 108,881 $ 2,449,300 $ 129,212 Earnings allocated to participating securities (6,676 ) (792 ) (12,426 ) (1,423 ) Net earnings available to common stockholders $ 1,500,192 $ 108,089 $ 2,436,874 $ 127,789 Basic average shares outstanding 296,817 302,921 299,359 302,915 Basic net earnings per share $ 5.05 $ 0.36 $ 8.14 $ 0.42 Diluted net earnings per share: Diluted net earnings $ 1,506,868 $ 108,881 $ 2,449,300 $ 129,212 Earnings allocated to participating securities (6,649 ) (792 ) (12,385 ) (1,423 ) Net earnings available to common stockholders $ 1,500,219 $ 108,089 $ 2,436,915 $ 127,789 Diluted average shares outstanding: Basic average shares outstanding 296,817 302,921 299,359 302,915 Dilutive effect of stock options and other 712 12 379 17 297,529 302,933 299,738 302,932 Diluted net earnings per share $ 5.04 $ 0.36 $ 8.13 $ 0.42
Anti-dilutive Stock Options	The following stock options were excluded from the computation of diluted net earnings per share for the second quarter and first six months of 2021 and 2020 because their effect would have been anti-dilutive (shares in thousands): Three Months (13 Weeks) Ended Six Months (26 Weeks) Ended July 3, 2021 July 4, 2020 July 3, 2021 July 4, 2020 Anti-dilutive stock options: Weighted-average shares 52 3,749 152 3,724 Weighted-average exercise price $ 110.74 $ 50.69 $ 73.47 $ 51.04

Inventories - Additional Inform

Inventories - Additional Information (Detail)	Jul. 03, 2021	Dec. 31, 2020
Inventory Disclosure [Abstract]
Raw materials and supplies in inventory, percentage	48.00%	42.00%
Finished and semi-finished products in inventory, percentage	52.00%	58.00%

Property, Plant and Equipment -

Property, Plant and Equipment - Additional Information (Detail) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 03, 2021USD ($)a	Jul. 04, 2020USD ($)	Jul. 03, 2021USD ($)a	Jul. 04, 2020USD ($)	Dec. 31, 2020USD ($)
Property, Plant and Equipment [Line Items]
Accumulated depreciation	$ 10,200,000		$ 10,200,000		$ 9,860,000
Property, plant and equipment, net	7,235,536		7,235,536		6,899,110
Losses on assets	44,308	$ 5,000	50,970	$ 292,846
Carrying Value of Three Groups of Wells [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, net	$ 68,400		$ 68,400		$ 71,700
Unproved Oil and Natural Gas Properties [Member]
Property, Plant and Equipment [Line Items]
Ownership percentage of leasehold interest in unproved oil and natural gas properties	49.00%		49.00%
Unproved oil and gas properties area | a	54,000		54,000
Unproved Oil and Gas Properties [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, net	$ 96,000		$ 96,000
Unproved Oil and Gas Properties [Member] | Losses on Assets [Member]
Property, Plant and Equipment [Line Items]
Losses on assets	$ 42,000		$ 42,000

Goodwill and Other Intangible_3

Goodwill and Other Intangible Assets - Schedule of Change in Net Carrying Amount of Goodwill by Segment (Detail) $ in Thousands	6 Months Ended
	Jul. 03, 2021USD ($)
Goodwill [Line Items]
Balance, beginning of period	$ 2,229,672
Acquisitions	705
Other	(129)
Translation	11,310
Balance, end of period	2,241,558
Steel Mills [Member]
Goodwill [Line Items]
Balance, beginning of period	612,470
Acquisitions	705
Balance, end of period	613,175
Steel Products [Member]
Goodwill [Line Items]
Balance, beginning of period	887,625
Other	(129)
Translation	11,310
Balance, end of period	898,806
Raw Materials [Member]
Goodwill [Line Items]
Balance, beginning of period	729,577
Balance, end of period	$ 729,577

Goodwill and Other Intangible_4

Goodwill and Other Intangible Assets - Additional Information (Detail) - USD ($)	3 Months Ended			6 Months Ended		12 Months Ended
	Jul. 03, 2021	Dec. 31, 2020	Jul. 04, 2020	Jul. 03, 2021	Jul. 04, 2020	Dec. 31, 2020
Finite And Indefinite Lived Intangible Assets [Line Items]
Impairment of goodwill		$ 0
Goodwill	$ 2,241,558,000	2,229,672,000		$ 2,241,558,000		$ 2,229,672,000
Finite-lived intangible assets	627,201,000	668,021,000		627,201,000		$ 668,021,000
Intangible asset amortization expense	20,800,000		$ 20,700,000	41,900,000	$ 42,200,000
Future amortization expense, in 2021	82,700,000			82,700,000
Future amortization expense, in 2022	81,100,000			81,100,000
Future amortization expense, in 2023	80,400,000			80,400,000
Future amortization expense, in 2024	79,600,000			79,600,000
Future amortization expense, in 2025	78,600,000			$ 78,600,000
Minimum [Member]
Finite And Indefinite Lived Intangible Assets [Line Items]
Intangible assets, useful life				5 years
Maximum [Member]
Finite And Indefinite Lived Intangible Assets [Line Items]
Intangible assets, useful life				22 years
Rebar Fabrication [Member]
Finite And Indefinite Lived Intangible Assets [Line Items]
Percentage of fair value exceeded carrying value						99.00%
Goodwill	374,100,000	364,300,000		$ 374,100,000		$ 364,300,000
Finite-lived intangible assets	55,200,000	58,800,000		55,200,000		$ 58,800,000
Grating unit [Member]
Finite And Indefinite Lived Intangible Assets [Line Items]
Percentage of fair value exceeded carrying value						88.00%
Goodwill	$ 37,400,000	$ 37,000,000		$ 37,400,000		$ 37,000,000

Goodwill and Other Intangible_5

Goodwill and Other Intangible Assets - Schedule of Intangible Assets (Detail) - USD ($) $ in Thousands	Jul. 03, 2021	Dec. 31, 2020
Finite-Lived Intangible Assets [Line Items]
Intangible assets, Gross Amount	$ 1,649,187	$ 1,648,149
Intangible assets, Accumulated Amortization	1,021,986	980,128
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, Gross Amount	1,422,758	1,421,962
Intangible assets, Accumulated Amortization	874,016	838,443
Trademarks and Trade Names [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, Gross Amount	162,608	162,365
Intangible assets, Accumulated Amortization	103,933	100,000
Other [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, Gross Amount	63,821	63,822
Intangible assets, Accumulated Amortization	$ 44,037	$ 41,685

Current Liabilities - Additiona

Current Liabilities - Additional Information (Detail) - USD ($) $ in Millions	Jul. 03, 2021	Dec. 31, 2020
Liabilities Current [Abstract]
Book overdrafts	$ 181.1	$ 210.5
Dividends payable, current	$ 120.1	$ 123.9

Fair Value Measurements - Sched

Fair Value Measurements - Schedule of Financial Assets and Liabilities Measured at Fair Value (Detail) - USD ($) $ in Thousands	Jul. 03, 2021	Dec. 31, 2020
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Short-term investments	$ 398,409	$ 408,004
Total assets	22,995,582	20,125,394
Reported Value Measurement [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents	2,204,795	2,186,820
Short-term investments	398,409	408,004
Restricted cash and cash equivalents	84,350	115,258
Derivative contracts, assets	6,800
Total assets	2,694,354	2,710,082
Derivative contracts, liabilities	(4,730)	(14,361)
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents	2,204,795	2,186,820
Short-term investments	398,409	408,004
Restricted cash and cash equivalents	84,350	115,258
Total assets	2,687,554	2,710,082
Significant Other Observable Inputs (Level 2) [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative contracts, assets	6,800
Total assets	6,800
Derivative contracts, liabilities	$ (4,730)	$ (14,361)

Fair Value Measurements - Addit

Fair Value Measurements - Additional Information (Detail) - USD ($) $ in Millions	Jul. 03, 2021	Dec. 31, 2020
Fair Value Disclosures [Abstract]
Fair value of short-term and long-term debt, including current maturities	$ 5,900	$ 6,050

Contingencies - Additional Info

Contingencies - Additional Information (Detail) - USD ($) $ in Millions	Jul. 03, 2021	Dec. 31, 2020
Commitments And Contingencies Disclosure [Abstract]
Accrual for environmental loss contingencies, gross	$ 14.2	$ 16
Accrued environmental loss contingencies, current	2.9	5.6
Accrued environmental loss contingencies, noncurrent	$ 11.3	$ 10.4

Stock-Based Compensation - Addi

Stock-Based Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		6 Months Ended
	Jul. 03, 2021	Jul. 04, 2020	Jul. 03, 2021	Jul. 04, 2020	May 14, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options exercise prices as percentage of the market value on the date of the grant			100.00%
Grant date fair value of stock options grant			$ 32.30
Compensation expenses for stock options	$ 2.6	$ 1.8	$ 2.9	$ 2.1
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options vesting period			3 years
Stock options term, years			10 years
Unrecognized compensation expense related to stock	4		$ 4
Weighted-average recognition period for unrecognized compensation expense related to stock (years)			2 years 4 months 24 days
Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense related to stock	63.6		$ 63.6
Weighted-average recognition period for unrecognized compensation expense related to stock (years)			1 year 6 months
Compensation expense	$ 22.7	26.8	$ 32	36.8
Omnibus Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock based compensation, common stock available for grant	7,000,000		7,000,000
Omnibus Plan [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock based compensation, common stock available for grant					19,000,000
Inactive Plans [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares reserved for future issuance	500,000		500,000
LTIP [Member] | Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Eligible age of officer for restricted stock award			55 years
AIP [Member] | Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Eligible age of officer for restricted stock award			55 years
Additional common stock units for election of deferred annual incentive award, percentage			25.00%
AIP and LTIP [Member] | Restricted Stock And Restricted Stock Units Member
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense related to stock	$ 2.1		$ 2.1
Weighted-average recognition period for unrecognized compensation expense related to stock (years)			1 year 10 months 24 days
Compensation expense	$ 21.6	$ 2.8	$ 31.8	$ 2.5

Stock-Based Compensation - Sche

Stock-Based Compensation - Schedule of Stock Option Plans Activity (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	6 Months Ended
	Jul. 03, 2021
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Outstanding at beginning of year, Shares	3,916
Granted, Shares	138
Exercised, Shares	(2,554)
Outstanding at end of year, Shares	1,500
Options exercisable at end of year, Shares	837
Outstanding at beginning of year, Weighted - Average Exercise Price	$ 50.03
Granted, Weighted - Average Exercise Price	110.74
Exercised, Weighted - Average Exercise Price	50.43
Outstanding at end of period, Weighted - Average Exercise Price	54.92
Options exercisable at end of year, Weighted - Average Exercise Price	$ 53.86
Outstanding, Weighted - Average Remaining Contractual Life	6 years 7 months 6 days
Stock options exercisable, Weighted - Average Remaining Contractual Life	4 years 9 months 18 days
Exercised, Aggregate Intrinsic Value	$ 49,707
Outstanding at end of year, Aggregate Intrinsic Value	64,347
Stock options exercisable, Aggregate Intrinsic Value	$ 35,916

Stock-Based Compensation - Sc_2

Stock-Based Compensation - Schedule of Grant Date Fair Value Black-Scholes Option-Pricing Model Assumptions (Detail)	6 Months Ended
	Jul. 03, 2021$ / shares
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Exercise price	$ 110.74
Expected dividend yield	1.46%
Expected stock price volatility	32.86%
Risk-free interest rate	1.28%
Expected life (years)	6 years 6 months

Stock-Based Compensation - Summ

Stock-Based Compensation - Summary of Nucor's RSU Activity (Detail) - Restricted Stock Units [Member] shares in Thousands	6 Months Ended
	Jul. 03, 2021$ / sharesshares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested at beginning of year, Shares | shares	1,830
Granted, Shares | shares	397
Vested, Shares | shares	(902)
Canceled, Shares | shares	(52)
Unvested at end of year, Shares | shares	1,273
Unvested at beginning of year, Grant Date Fair Value | $ / shares	$ 47.33
Granted, Grant Date Fair Value | $ / shares	110.74
Vested, Grant Date Fair Value | $ / shares	57.40
Canceled, Grant Date Fair Value | $ / shares	47.62
Unvested at end of year, Grant Date Fair Value | $ / shares	$ 59.97

Stock-Based Compensation - Su_2

Stock-Based Compensation - Summary of Nucor's Restricted Stock Activity under AIP and LTIP (Detail) - Restricted Stock Units and Restricted Stock Awards [Member] shares in Thousands	6 Months Ended
	Jul. 03, 2021$ / sharesshares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested at beginning of year, Shares | shares	127
Granted, Shares | shares	262
Vested, Shares | shares	(240)
Canceled, Shares | shares	(9)
Unvested at end of year, Shares | shares	140
Unvested at beginning of year, Grant Date Fair Value | $ / shares	$ 49.94
Granted, Grant Date Fair Value | $ / shares	65.61
Vested, Grant Date Fair Value | $ / shares	63.10
Canceled, Grant Date Fair Value | $ / shares	48.75
Unvested at end of year, Grant Date Fair Value | $ / shares	$ 56.77

Employee Benefit Plan - Additio

Employee Benefit Plan - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jul. 03, 2021	Jul. 04, 2020	Jul. 03, 2021	Jul. 04, 2020
Employee Benefit Plan [Abstract]
Profit Sharing and Retirement Savings Plan, plan expense	$ 192.4	$ 20.4	$ 321.3	$ 32

Interest Expense (Income) - Sch

Interest Expense (Income) - Schedule of Components of Net Interest Expense (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 03, 2021	Jul. 04, 2020	Jul. 03, 2021	Jul. 04, 2020
Interest Revenue Or Expense Net [Abstract]
Interest expense	$ 37,661	$ 38,849	$ 78,631	$ 86,445
Interest income	(1,881)	(3,042)	(3,207)	(9,728)
Interest expense, net	$ 35,780	$ 35,807	$ 75,424	$ 76,717

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended
	Jul. 03, 2021	Jul. 04, 2020	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Effective income tax rate	22.40%	26.50%
Unfavorable non-cash out-of-period adjustment to deferred tax balances		$ 5.3
Non-current deferred tax liabilities included in deferred credits and other liabilities	$ 701.9		$ 596.4

Stockholders' Equity - Addition

Stockholders' Equity - Additional Information (Detail) - USD ($)	3 Months Ended		6 Months Ended
	Jul. 03, 2021	Jul. 04, 2020	Jul. 03, 2021	Jul. 04, 2020	May 13, 2021
Dividends declared per share	$ 0.405	$ 0.4025	$ 0.81	$ 0.805
Common Stock [Member]
Share repurchase program, available repurchase amount	$ 2,800,000,000		$ 2,800,000,000
Common Stock [Member] | Maximum [Member]
Stock Repurchase Program, Authorized Amount					$ 3,000,000,000
Nucor-Yamato Steel Company [Member]
Noncontrolling interest, ownership percentage by parent	51.00%	51.00%	51.00%	51.00%

Stockholders' Equity - Schedule

Stockholders' Equity - Schedule of Change in Stockholder's Equity (Detail) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 03, 2021	Jul. 04, 2020	Jul. 03, 2021	Jul. 04, 2020
BALANCES, beginning of period	$ 11,861,723	$ 10,596,069	$ 11,231,861	$ 10,791,176
Net earnings	1,571,459	133,153	2,558,973	187,532
Other comprehensive income (loss)	29,831	26,791	45,132	(37,870)
Stock options exercised	21,276		$ 128,800
Stock options exercised (in shares)			2,554
Stock option expense	2,575	1,864	$ 2,908	2,139
Issuance of stock under award plans, net of forfeitures	(18,338)	11,618	(2,736)	27,807
Amortization of unearned compensation	(1,100)	500	800	900
Treasury stock value acquired	(614,286)		(916,145)	(39,499)
Cash dividends declared	(120,088)	(123,038)	(242,746)	(245,735)
Distributions to noncontrolling interests	(23,401)	(23,472)	(97,196)	(62,965)
BALANCES, end of period	12,709,651	10,623,485	12,709,651	10,623,485
Common Stock [Member]
BALANCES, beginning of period	$ 152,061	$ 152,061	$ 152,061	$ 152,061
BALANCES, shares at beginning of period	380,154	380,154	380,154	380,154
BALANCES, end of period	$ 152,061	$ 152,061	$ 152,061	$ 152,061
BALANCES, shares at end of period	380,154	380,154	380,154	380,154
Additional Paid-in Capital [Member]
BALANCES, beginning of period	$ 2,160,909	$ 2,119,370	$ 2,121,288	$ 2,107,646
Stock options exercised	5,337		35,825
Stock option expense	2,575	1,864	2,908	2,139
Issuance of stock under award plans, net of forfeitures	(50,566)	(14,827)	(43,666)	(3,778)
Amortization of unearned compensation	(1,100)	500	800	900
BALANCES, end of period	2,117,155	2,106,907	2,117,155	2,106,907
Retained Earnings [Member]
BALANCES, beginning of period	12,163,626	11,012,690	11,343,852	11,115,056
Net earnings	1,506,868	108,881	2,449,300	129,212
Cash dividends declared	(120,088)	(123,038)	(242,746)	(245,735)
BALANCES, end of period	13,550,406	10,998,533	13,550,406	10,998,533
Accumulated Other Comprehensive Income (Loss) [Member]
BALANCES, beginning of period	(103,560)	(367,627)	(118,861)	(302,966)
Other comprehensive income (loss)	29,831	26,791	45,132	(37,870)
BALANCES, end of period	(73,729)	(340,836)	(73,729)	(340,836)
Treasury Stock (at cost) [Member]
BALANCES, beginning of period	$ (2,925,796)	$ (2,748,290)	$ (2,709,675)	$ (2,713,931)
BALANCES, shares at beginning of period	80,912	79,019	77,909	78,342
Stock options exercised	$ 15,939		$ 92,975
Stock options exercised (in shares)	(419)		(2,554)
Issuance of stock under award plans, net of forfeitures	$ 32,228	$ 26,445	$ 40,930	$ 31,585
Issuance of stock under award plans, net of forfeitures, shares	(799)	(760)	(1,041)	(908)
Treasury stock value acquired	$ (614,286)		$ (916,145)	$ (39,499)
Treasury stock acquired (in shares)	6,765		12,145	825
BALANCES, end of period	$ (3,491,915)	$ (2,721,845)	$ (3,491,915)	$ (2,721,845)
BALANCES, shares at end of period	86,459	78,259	86,459	78,259
Total Nucor Stockholders' Equity [Member]
BALANCES, beginning of period	$ 11,447,240	$ 10,168,204	$ 10,788,665	$ 10,357,866
Net earnings	1,506,868	108,881	2,449,300	129,212
Other comprehensive income (loss)	29,831	26,791	45,132	(37,870)
Stock options exercised	21,276		128,800
Stock option expense	2,575	1,864	2,908	2,139
Issuance of stock under award plans, net of forfeitures	(18,338)	11,618	(2,736)	27,807
Amortization of unearned compensation	(1,100)	500	800	900
Treasury stock value acquired	(614,286)		(916,145)	(39,499)
Cash dividends declared	(120,088)	(123,038)	(242,746)	(245,735)
BALANCES, end of period	12,253,978	10,194,820	12,253,978	10,194,820
Noncontrolling Interests [Member]
BALANCES, beginning of period	414,483	427,865	443,196	433,310
Net earnings	64,591	24,272	109,673	58,320
Distributions to noncontrolling interests	(23,401)	(23,472)	(97,196)	(62,965)
BALANCES, end of period	$ 455,673	$ 428,665	$ 455,673	$ 428,665

Accumulated Other Comprehensi_3

Accumulated Other Comprehensive Income (Loss) - Components of Accumulated Other Comprehensive Income (Loss) (Detail) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Jul. 03, 2021		Jul. 04, 2020		Jul. 03, 2021		Jul. 04, 2020
Accumulated Other Comprehensive Income Loss Net Of Tax [Abstract]
Beginning Balance, Gains and (Losses) on Hedging Derivatives	$ (3,200)		$ (14,200)		$ (4,700)		$ (14,000)
Other comprehensive income (loss) before reclassifications, Gains and (Losses) on Hedging Derivatives	8,204		757		9,203		(1,499)
Amounts reclassified from accumulated other comprehensive (loss) income into earnings, Gains and (Losses) on Hedging Derivatives	196	[1]	2,543	[2]	697	[1]	4,599	[2]
Net current-period other comprehensive income (loss), Gains and (Losses) on Hedging Derivatives	8,400		3,300		9,900		3,100
Ending Balance, Gains and (Losses) on Hedging Derivatives	5,200		(10,900)		5,200		(10,900)
Beginning Balance, Foreign Currency Gains (Loss)	(107,026)		(361,234)		(120,827)		(296,773)
Other comprehensive income (loss) before reclassifications, Foreign Currency Gains (Loss)	21,431		23,491		35,232		(40,970)
Net current-period other comprehensive income (loss), Foreign Currency Gains (Loss)	21,431		23,491		35,232		(40,970)
Ending Balance, Foreign Currency Gains (Loss)	(85,595)		(337,743)		(85,595)		(337,743)
Beginning Balance, Adjustment to Early Retiree Medical Plan	6,666		7,807		6,666		7,807
Ending Balance, Adjustment to Early Retiree Medical Plan	6,666		7,807		6,666		7,807
Beginning Balance	(103,560)		(367,627)		(118,861)		(302,966)
Other comprehensive income (loss) before reclassifications	29,635		24,248		44,435		(42,469)
Amounts reclassified from accumulated other comprehensive income (loss) into earnings	196	[1]	2,543	[2]	697	[1]	4,599	[2]
Net current-period other comprehensive income (loss)	29,831		26,791		45,132		(37,870)
Ending Balance	$ (73,729)		$ (340,836)		$ (73,729)		$ (340,836)
[1]	Includes $196 and $697 of accumulated other comprehensive income (loss) reclassifications into cost of products sold for net losses on commodity contracts in the second quarter and first six months of 2021, respectively. The tax impact of those reclassifications was $0 and $100 in the second quarter and first six months of 2021, respectively.
[2]	Includes $2,543 and $4,599 of accumulated other comprehensive income (loss) reclassifications into cost of products sold for net losses on commodity contracts in the second quarter and first six months of 2020, respectively. The tax impact of those reclassifications was $900 and $1,600 in the second quarter and first six months of 2020, respectively.

Accumulated Other Comprehensi_4

Accumulated Other Comprehensive Income (Loss) - Components of Accumulated Other Comprehensive Income (Loss) (Parenthetical) (Detail) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Jul. 03, 2021		Jul. 04, 2020		Jul. 03, 2021		Jul. 04, 2020
Accumulated Other Comprehensive Income (Loss) [Line Items]
Amounts reclassified from accumulated other comprehensive (loss) income into earnings, Gains and (Losses) on Hedging Derivatives	$ 196	[1]	$ 2,543	[2]	$ 697	[1]	$ 4,599	[2]
AOCI reclassification impact on tax	0		900		100		1,600
Cost of Products Sold [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Amounts reclassified from accumulated other comprehensive (loss) income into earnings, Gains and (Losses) on Hedging Derivatives	196		2,543		697		4,599
AOCI reclassification impact on tax	$ 0		$ 900		$ 100		$ 1,600
[1]	Includes $196 and $697 of accumulated other comprehensive income (loss) reclassifications into cost of products sold for net losses on commodity contracts in the second quarter and first six months of 2021, respectively. The tax impact of those reclassifications was $0 and $100 in the second quarter and first six months of 2021, respectively.
[2]	Includes $2,543 and $4,599 of accumulated other comprehensive income (loss) reclassifications into cost of products sold for net losses on commodity contracts in the second quarter and first six months of 2020, respectively. The tax impact of those reclassifications was $900 and $1,600 in the second quarter and first six months of 2020, respectively.

Segments - Segments (Detail)

Segments - Segments (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 03, 2021	Jul. 04, 2020	Jul. 03, 2021	Jul. 04, 2020	Dec. 31, 2020
Segment Reporting Information [Line Items]
Net sales	$ 8,789,164	$ 4,327,306	$ 15,806,304	$ 9,951,643
Earnings (loss) before income taxes and noncontrolling interests	2,025,748	181,057	3,323,994	327,354
Total assets	22,995,582		22,995,582		$ 20,125,394
Operating Segments [Member] | Steel Mills [Member]
Segment Reporting Information [Line Items]
Net sales	5,909,909	2,513,961	10,518,686	6,033,231
Earnings (loss) before income taxes and noncontrolling interests	2,174,807	150,424	3,489,781	306,930
Total assets	11,734,231		11,734,231		9,708,260
Operating Segments [Member] | Steel Products [Member]
Segment Reporting Information [Line Items]
Net sales	2,241,107	1,523,168	4,051,162	3,250,022
Earnings (loss) before income taxes and noncontrolling interests	259,330	152,874	471,142	315,433
Total assets	5,342,505		5,342,505		4,461,042
Operating Segments [Member] | Raw Materials [Member]
Segment Reporting Information [Line Items]
Net sales	638,148	290,177	1,236,456	668,390
Earnings (loss) before income taxes and noncontrolling interests	120,143	(1,389)	343,378	(9,300)
Total assets	3,876,540		3,876,540		3,324,489
Intercompany Eliminations [Member] | Steel Mills [Member]
Segment Reporting Information [Line Items]
Net sales	1,496,298	663,244	2,721,411	1,532,336
Intercompany Eliminations [Member] | Steel Products [Member]
Segment Reporting Information [Line Items]
Net sales	80,394	63,205	151,613	146,574
Intercompany Eliminations [Member] | Raw Materials [Member]
Segment Reporting Information [Line Items]
Net sales	4,009,808	1,484,982	7,656,003	3,908,787
Corporate and Eliminations Items [Member]
Segment Reporting Information [Line Items]
Net sales	(5,586,500)	(2,211,431)	(10,529,027)	(5,587,697)
Earnings (loss) before income taxes and noncontrolling interests	(528,532)	$ (120,852)	(980,307)	$ (285,709)
Total assets	$ 2,042,306		$ 2,042,306		$ 2,631,603

Revenue - Schedule of Net Sales

Revenue - Schedule of Net Sales Disaggregates by Major Source (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 03, 2021	Jul. 04, 2020	Jul. 03, 2021	Jul. 04, 2020
Revenue from Contract with Customers [Line Items]
Revenues	$ 8,789,164	$ 4,327,306	$ 15,806,304	$ 9,951,643
Sheet [Member]
Revenue from Contract with Customers [Line Items]
Revenues	3,104,304	1,065,004	5,455,759	2,643,433
Bar [Member]
Revenue from Contract with Customers [Line Items]
Revenues	1,515,115	811,054	2,776,157	1,873,720
Structural [Member]
Revenue from Contract with Customers [Line Items]
Revenues	619,541	347,258	1,096,736	797,757
Plate [Member]
Revenue from Contract with Customers [Line Items]
Revenues	670,949	290,645	1,190,034	718,321
Tubular Products [Member]
Revenue from Contract with Customers [Line Items]
Revenues	512,503	250,311	887,156	555,368
Rebar Fabrication [Member]
Revenue from Contract with Customers [Line Items]
Revenues	480,727	413,916	867,284	837,232
Other Steel Products [Member]
Revenue from Contract with Customers [Line Items]
Revenues	1,247,877	858,941	2,296,722	1,857,422
Raw Materials [Member]
Revenue from Contract with Customers [Line Items]
Revenues	638,148	290,177	1,236,456	668,390
Steel Mills [Member]
Revenue from Contract with Customers [Line Items]
Revenues	5,909,909	2,513,961	10,518,686	6,033,231
Steel Mills [Member] | Sheet [Member]
Revenue from Contract with Customers [Line Items]
Revenues	3,104,304	1,065,004	5,455,759	2,643,433
Steel Mills [Member] | Bar [Member]
Revenue from Contract with Customers [Line Items]
Revenues	1,515,115	811,054	2,776,157	1,873,720
Steel Mills [Member] | Structural [Member]
Revenue from Contract with Customers [Line Items]
Revenues	619,541	347,258	1,096,736	797,757
Steel Mills [Member] | Plate [Member]
Revenue from Contract with Customers [Line Items]
Revenues	670,949	290,645	1,190,034	718,321
Steel Products [Member]
Revenue from Contract with Customers [Line Items]
Revenues	2,241,107	1,523,168	4,051,162	3,250,022
Steel Products [Member] | Tubular Products [Member]
Revenue from Contract with Customers [Line Items]
Revenues	512,503	250,311	887,156	555,368
Steel Products [Member] | Rebar Fabrication [Member]
Revenue from Contract with Customers [Line Items]
Revenues	480,727	413,916	867,284	837,232
Steel Products [Member] | Other Steel Products [Member]
Revenue from Contract with Customers [Line Items]
Revenues	1,247,877	858,941	2,296,722	1,857,422
Raw Materials [Member]
Revenue from Contract with Customers [Line Items]
Revenues	638,148	290,177	1,236,456	668,390
Raw Materials [Member] | Raw Materials [Member]
Revenue from Contract with Customers [Line Items]
Revenues	$ 638,148	$ 290,177	$ 1,236,456	$ 668,390

Revenue - Additional Informatio

Revenue - Additional Information (Detail) - USD ($) $ in Millions	Jul. 03, 2021	Dec. 31, 2020
Revenue From Contract With Customer [Abstract]
Contract liabilities	$ 159.2	$ 120.2

Earnings Per Share - Computatio

Earnings Per Share - Computations of Basic and Diluted Net Earnings Per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 03, 2021	Jul. 04, 2020	Jul. 03, 2021	Jul. 04, 2020
Earnings Per Share [Abstract]
Basic net earnings	$ 1,506,868	$ 108,881	$ 2,449,300	$ 129,212
Earnings allocated to participating securities, Basic	(6,676)	(792)	(12,426)	(1,423)
Net earnings available to common stockholders, Basic	$ 1,500,192	$ 108,089	$ 2,436,874	$ 127,789
Basic average shares outstanding	296,817	302,921	299,359	302,915
Basic net earnings per share	$ 5.05	$ 0.36	$ 8.14	$ 0.42
Diluted net earnings	$ 1,506,868	$ 108,881	$ 2,449,300	$ 129,212
Earnings allocated to participating securities, Diluted	(6,649)	(792)	(12,385)	(1,423)
Net earnings available to common stockholders, Diluted	$ 1,500,219	$ 108,089	$ 2,436,915	$ 127,789
Dilutive effect of stock options and other	712	12	379	17
Diluted average shares outstanding	297,529	302,933	299,738	302,932
Diluted net earnings per share	$ 5.04	$ 0.36	$ 8.13	$ 0.42

Earnings Per Share - Anti-dilut

Earnings Per Share - Anti-dilutive Stock Options (Detail) - $ / shares shares in Thousands	3 Months Ended		6 Months Ended
	Jul. 03, 2021	Jul. 04, 2020	Jul. 03, 2021	Jul. 04, 2020
Earnings Per Share [Abstract]
Weighted-average shares	52	3,749	152	3,724
Weighted-average exercise price	$ 110.74	$ 50.69	$ 73.47	$ 51.04

Subsequent Events - Additional

Subsequent Events - Additional Information (Details) - Subsequent Events [Member] $ in Millions	Aug. 09, 2021USD ($)Facility	Aug. 04, 2021USD ($)	Jul. 20, 2021USD ($)Facility
40-year Variable-rate Green Bonds [Member]
Subsequent Event [Line Items]
Issuance of Bonds		$ 197
Cornerstone Building Brands, Inc., Insulated Metal Panels ("IMP") [Member]
Subsequent Event [Line Items]
Business acquisition, cash purchase price	$ 1,000
Cornerstone Building Brands, Inc., Insulated Metal Panels ("IMP") [Member] | North America [Member]
Subsequent Event [Line Items]
Business acquisition, Number of facilities | Facility	7
Hannibal Industries [Member]
Subsequent Event [Line Items]
Business acquisition, cash purchase price			$ 370
Business acquisition, number of distribution facilities | Facility			3