Nucor (NUE) 10-Q 12 Nov 20 2020 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information	9 Months Ended
	Oct. 03, 2020shares
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Oct. 3, 2020
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q3
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	301,928,935

Condensed Consolidated Statemen

Condensed Consolidated Statements of Earnings - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 03, 2020	Sep. 28, 2019	Oct. 03, 2020	Sep. 28, 2019
Income Statement [Abstract]
Net sales	$ 4,927,960	$ 5,464,502	$ 14,879,603	$ 17,457,112
Costs, expenses and other:
Cost of products sold	4,425,765	4,891,991	13,370,181	15,213,215
Marketing, administrative and other expenses	165,513	159,301	460,922	549,020
Equity in losses (earnings) of unconsolidated affiliates	(479)	1,585	14,422	(2,459)
Losses on assets	6,604		299,450
Interest expense, net	40,139	31,286	116,856	92,759
Costs, expenses and other, total	4,637,542	5,084,163	14,261,831	15,852,535
Earnings before income taxes and noncontrolling interests	290,418	380,339	617,772	1,604,577
Provision for income taxes	67,788	86,752	207,610	367,920
Net earnings	222,630	293,587	410,162	1,236,657
Earnings attributable to noncontrolling interests	29,215	18,556	87,535	73,337
Net earnings attributable to Nucor stockholders	$ 193,415	$ 275,031	$ 322,627	$ 1,163,320
Net earnings per share:
Basic	$ 0.63	$ 0.90	$ 1.06	$ 3.79
Diluted	$ 0.63	$ 0.90	$ 1.06	$ 3.78
Average shares outstanding:
Basic	303,394	304,637	303,072	305,553
Diluted	303,441	304,980	303,099	306,029

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended				9 Months Ended
	Oct. 03, 2020		Sep. 28, 2019		Oct. 03, 2020		Sep. 28, 2019
Statement Of Comprehensive Income [Abstract]
Net earnings	$ 222,630		$ 293,587		$ 410,162		$ 1,236,657
Other comprehensive income:
Net unrealized income (loss) on hedging derivatives, net of income taxes of $2,000 and $(1,000) for the third quarter of 2020 and 2019, respectively, and $1,400 and $(2,500) for the first nine months of 2020 and 2019, respectively	6,387		(3,315)		4,888		(7,801)
Reclassification adjustment for settlement of hedging derivatives included in net income, net of income taxes of $700 and $500 for the third quarter of 2020 and 2019, respectively, and $2,300 and $500 for the first nine months of 2020 and 2019, respectively	2,113	[1]	1,615	[2]	6,712	[1]	1,501	[2]
Foreign currency translation gain (loss), net of income taxes of $0 for the third quarter and first nine months of 2020 and 2019	16,867		(14,306)		(24,103)		(5,219)
Net current-period other comprehensive income (loss)	25,367		(16,006)		(12,503)		(11,519)
Comprehensive income	247,997		277,581		397,659		1,225,138
Comprehensive income attributable to noncontrolling interests	(29,215)		(18,556)		(87,535)		(73,337)
Comprehensive income attributable to Nucor stockholders	$ 218,782		$ 259,025		$ 310,124		$ 1,151,801
[1]	Includes $2,113 and $6,712 of accumulated other comprehensive income (loss) reclassifications into cost of products sold for net losses on commodity contracts in the third quarter and first nine months of 2020, respectively. The tax impacts of those reclassifications were $700 and $2,300 in the third quarter and first nine months of 2020, respectively.
[2]	Includes $1,615 and $1,501 of accumulated other comprehensive income (loss) reclassifications into cost of products sold for net losses on commodity contracts in the third quarter and first nine months of 2019, respectively. The tax impacts of those reclassifications were $500 in both the third quarter and first nine months of 2019.

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Comprehensive Income (Parenthetical) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 03, 2020	Sep. 28, 2019	Oct. 03, 2020	Sep. 28, 2019
Statement Of Comprehensive Income [Abstract]
Net unrealized income (loss) on hedging derivatives, tax	$ 2,000	$ (1,000)	$ 1,400	$ (2,500)
Reclassification adjustment for settlement of hedging derivatives included in net income, tax effect	700	500	2,300	500
Foreign currency translation gain (loss), tax	$ 0	$ 0	$ 0	$ 0

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Oct. 03, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 2,866,578	$ 1,534,605
Short-term investments	412,401	300,040
Accounts receivable, net	2,119,421	2,160,102
Inventories, net	3,260,685	3,842,095
Other current assets	306,762	389,528
Total current assets	8,965,847	8,226,370
Property, plant and equipment, net	6,829,733	6,178,555
Restricted cash and cash equivalents	131,623
Goodwill	2,195,788	2,201,063
Other intangible assets, net	678,558	742,186
Other assets	717,728	996,492
Total assets	19,519,277	18,344,666
Current liabilities:
Short-term debt	63,778	62,444
Current portion of long-term debt and finance lease obligations	10,475	29,264
Accounts payable	1,210,987	1,201,698
Salaries, wages and related accruals	432,767	510,844
Accrued expenses and other current liabilities	655,288	659,524
Total current liabilities	2,373,295	2,463,774
Long-term debt and finance lease obligations due after one year	5,452,193	4,291,301
Deferred credits and other liabilities	976,722	798,415
Total liabilities	8,802,210	7,553,490
Nucor stockholders' equity:
Common stock	152,061	152,061
Additional paid-in capital	2,117,582	2,107,646
Retained earnings	11,068,908	11,115,056
Accumulated other comprehensive loss, net of income taxes	(315,469)	(302,966)
Treasury stock	(2,720,668)	(2,713,931)
Total Nucor stockholders' equity	10,302,414	10,357,866
Noncontrolling interests	414,653	433,310
Total equity	10,717,067	10,791,176
Total liabilities and equity	$ 19,519,277	$ 18,344,666

Condensed Consolidated Statem_4

Condensed Consolidated Statements of Cash Flows $ in Thousands	9 Months Ended
	Oct. 03, 2020USD ($)	Sep. 28, 2019USD ($)
Operating activities:
Net earnings	$ 410,162	$ 1,236,657
Adjustments:
Depreciation	525,688	477,957
Amortization	62,877	64,655
Stock-based compensation	56,122	74,311
Deferred income taxes	140,606	76,737
Distributions from affiliates	3,021	27,405
Equity in losses (earnings) of unconsolidated affiliates	14,422	(2,459)
Losses on assets	299,450
Changes in assets and liabilities (exclusive of acquisitions and dispositions):
Accounts receivable	37,547	197,783
Inventories	590,434	476,761
Accounts payable	15,366	(180,397)
Federal income taxes	18,848	(177,405)
Salaries, wages and related accruals	(69,235)	(157,317)
Other operating activities	100,283	5,526
Cash provided by operating activities	2,205,591	2,120,214
Investing activities:
Capital expenditures	(1,179,081)	(984,646)
Investment in and advances to affiliates	(16,542)	(27,613)
Divestiture of affiliates		67,591
Disposition of plant and equipment	19,492	32,922
Acquisitions (net of cash acquired)	(20,368)	(9,495)
Purchase of investments	(401,986)	(249,616)
Proceeds from the sale of investments	301,249
Other investing activities	(33,536)	2,176
Cash used in investing activities	(1,330,772)	(1,168,681)
Financing activities:
Net change in short-term debt	1,334	(10,145)
Proceeds from long-term debt, net of discount	1,237,635
Repayment of long-term debt	(97,150)
Bond issuance related costs	(6,250)
Issuance of common stock		5,892
Payment of tax withholdings on certain stock-based compensation	(17,691)	(15,723)
Distributions to noncontrolling interests	(106,193)	(71,241)
Cash dividends	(368,636)	(369,270)
Acquisition of treasury stock	(39,499)	(197,511)
Other financing activities	(6,983)	(6,538)
Cash provided by (used in) financing activities	596,567	(664,536)
Effect of exchange rate changes on cash	(7,790)	482
Increase in cash and cash equivalents	1,463,596	287,479
Cash and cash equivalents - beginning of year	1,534,605	1,398,886
Cash and cash equivalents and restricted cash and cash equivalents - end of nine months	$ 2,998,201	1,686,365
Non-cash investing activity:
Change in accrued plant and equipment purchases		$ 62,700

Basis of Interim Presentation

Basis of Interim Presentation	9 Months Ended
	Oct. 03, 2020
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, 2019 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, 2019.

Inventories

Inventories	9 Months Ended
	Oct. 03, 2020
Inventory Disclosure [Abstract]
Inventories	2. Inventories Inventories consisted of approximately 40% raw materials and supplies and 60% finished and semi-finished products at October 3, 2020 (42% and 58%, respectively, at December 31, 2019). 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	9 Months Ended
	Oct. 03, 2020
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 $9.87 billion at October 3, 2020 ($9.42 billion at December 31, 2019). Nucor performed an impairment assessment of its proved producing natural gas well assets in the fourth quarter of 2019. One of the main assumptions that most significantly affects the undiscounted cash flows determination used in the impairment assessment is management’s As a result of the impairment assessment, Nucor recorded a non-cash impairment charge of $35.0 million relating to one field of wells in the fourth quarter of 2019. The post-impairment carrying value of this field was $11.2 million Changes in the natural gas industry or a prolonged low-price environment beyond what had already been assumed in the assessments could cause management to revise the natural gas and natural gas liquids price assumptions, the estimated reserves or the estimated lease operating costs. Unfavorable revisions to these assumptions or estimates could possibly result in further impairment of some or all of the fields of proved well assets. 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. The carrying value of the entire leasehold interest at October 3, 2020 was $165.0 million. Nucor has full discretion on its participation in all future drilling capital investments related to the leasehold interest.

Goodwill and Other Intangible A

Goodwill and Other Intangible Assets	9 Months Ended
	Oct. 03, 2020
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 nine months ended October 3, 2020 by segment was as follows (in thousands): Steel Mills Steel Products Raw Materials Total Balance at December 31, 2019 $ 591,986 $ 879,500 $ 729,577 $ 2,201,063 Other - (821 ) - (821 ) Translation - (4,454 ) - (4,454 ) Balance at October 3, 2020 $ 591,986 $ 874,225 $ 729,577 $ 2,195,788 Nucor completed its most recent annual goodwill impairment testing during the fourth quarter of 2019 and concluded that as of such time there was no impairment of goodwill for any of its reporting units. The assessment performed in 2019 used forward-looking projections and included expected improvements in the future cash flows of one of the Company’s reporting units, Rebar Fabrication. The fair value of this reporting unit exceeded its carrying value by approximately 56% in the most recent assessment. The reporting unit’s profitability in the first nine months of 2020 significantly increased from the first nine months of 2019. We expect the 2020 operating results of the Rebar Fabrication reporting unit will continue to improve compared to 2019. 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 $352.7 million as of October 3, 2020 ($356.6 million as of December 31, 2019). 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 $59.6 million as of October 3, 2020 ($67.2 million as of December 31, 2019). 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. Due to lower than expected operating results and anticipated changes to the Grating reporting unit’s business strategy and structure, the Company determined a triggering event occurred in the third quarter of 2019 and performed an impairment assessment. The fair value of the Grating reporting unit exceeded its carrying value by approximately 17% in that 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 $36.6 million as of October 3, 2020 ($36.8 million as of December 31, 2019). 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 October 3, 2020 and December 31, 2019 (in thousands): October 3, 2020 December 31, 2019 Gross Amount Accumulated Amortization Gross Amount Accumulated Amortization Customer relationships $ 1,412,323 $ 821,029 $ 1,412,954 $ 767,532 Trademarks and trade names 162,062 98,110 162,183 92,258 Other 63,822 40,510 63,807 36,968 $ 1,638,207 $ 959,649 $ 1,638,944 $ 896,758 Intangible asset amortization expense in the third quarter of 2020 and 2019 was $20.7 million and $22.0 million, respectively, and was $62.9 million and $64.7 million in the first nine months of 2020 and 2019, respectively. Annual amortization expense is estimated to be $83.5 million in 2020; $82.3 million in 2021; $80.7 million in 2022; $80.0 million in 2023; and $79.2 million in 2024.

Equity Investments

Equity Investments	9 Months Ended
	Oct. 03, 2020
Equity Method Investments And Joint Ventures [Abstract]
Equity Investments	5. Equity Investments The carrying value of our equity investments in domestic and foreign companies was $521.2 million at October 3, 2020 ($793.2 million at December 31, 2019) and is recorded in other assets in the condensed consolidated balance sheets. NuMit Nucor owns a 50% economic and voting interest in NuMit LLC (“NuMit”). NuMit owns 100% of the equity interest in Steel Technologies LLC, an operator of 26 sheet processing facilities located throughout the United States, Canada and Mexico. Nucor accounts for its investment in NuMit (on a one-month lag basis) under the equity method, as control and risk of loss are shared equally between the members of NuMit . Nucor’s investment in NuMit was $ 322.5 million at October 3, 2020 ($ 319.8 million at December 31, 2019 ). Nucor received distributions of $ 2.0 million and $ 27.4 million from NuMit during the first nine months of 2020 and 2019 , respectively. Duferdofin Nucor Nucor owns a 50% economic and voting interest in Duferdofin Nucor S.r.l. (“Duferdofin Nucor”), an Italian steel manufacturer, and accounts for its investment (on a one-month Nucor’s investment in Duferdofin Nucor was $0.1 million at October 3, 2020 ($263.0 million at December 31, 2019). Nucor’s 50% share of the total net assets of Duferdofin Nucor was $128.6 million at October 3, 2020, resulting in a negative basis difference of $128.5 million. This was due to the $261.6 million impairment charge taken against the Company’s investment in Duferdofin Nucor in the first nine months of 2020 as discussed below, offset by the step-up to fair value of certain assets and liabilities attributable to Duferdofin Nucor, as well as the identification of goodwill ($86.5 million at December 31, 2019) and finite-lived intangible assets. This basis difference prior to the impairment charge, excluding the portion attributable to goodwill, was being amortized based on the remaining estimated useful lives of the various underlying net assets, as appropriate, through the first quarter of 2020. Beginning with the second quarter of 2020, the negative basis difference began amortizing based on the remaining estimated useful lives of the various underlying net assets, as appropriate. Amortization associated with the negative basis in the third quarter of 2020 was income of $1.9 million, compared to an expense of $2.2 million in the third quarter of 2019, associated with the fair value step-up. Net amortization was $1.6 million of income in the first nine months of 2020, and $6.7 million of expense in the first nine months 2019. As of October 3, 2020, Nucor had outstanding notes receivable of €35.0 million ($41.0 million) from Duferdofin Nucor (€35.0 million, or $39.3 million, as of December 31, 2019). The notes receivable bear interest at a rate that resets annually on September 30 to the 12-month Euro Interbank Offered Rate plus 0.75% per year. The maturity date of the principal amounts is January 31, 2022. As of October 3, 2020 and December 31, 2019, the notes receivable were classified in other assets in the condensed consolidated balance sheets. These notes were fully reserved in connection with the $261.6 million impairment charge taken against the Company’s investment in Duferdofin Nucor in the first nine months of 2020. Nucor has issued a guarantee for its ownership percentage (50%) of Duferdofin Nucor’s borrowings under Facility A of a Structured Trade Finance Facilities Agreement (“Facility A”). The fair value of the guarantee is immaterial. In April 2018, Duferdofin Nucor amended and extended Facility A to mature on April 16, 2021. The maximum amount Duferdofin Nucor could borrow under Facility A was €160.0 million ($187.5 million) at October 3, 2020. As of October 3, 2020, there was €132.0 million ($154.7 million) outstanding under that facility (€147.0 million, or $164.9 million, as of December 31, 2019). If Duferdofin Nucor fails to pay when due any amounts for which it is obligated under Facility A, Nucor could be required to pay 50% of such amounts pursuant to and in accordance with the terms of its guarantee. Any indebtedness of Duferdofin Nucor to Nucor is effectively subordinated to the indebtedness of Duferdofin Nucor under Facility A. Nucor has not recorded any liability associated with this guarantee. On October 2, 2020, Nucor entered into an agreement (the “Duferdofin Agreement”) to transfer its 50% economic and voting interest in Duferdofin Nucor to the owner of the remaining 50% interest. The closing of the transaction is subject to Duferdofin Nucor renegotiating the borrowings currently under Facility A, Nucor’s relief under the guarantee and other customary closing conditions, including regulatory consents. The closing of the transaction is expected to occur during the fourth quarter of 2020. Nucor is continuing to evaluate the impact of the transaction contemplated by the Duferdofin Agreement on the financial statements, which will include foreign currency losses currently included in accumulated other comprehensive loss as outlined in Footnote 14 and other impacts. Nucor-JFE Nucor owns a 50% economic and voting interest in Nucor-JFE Steel Mexico, S. de R.L. de C.V. (“Nucor-JFE”), a 50-50 joint venture with JFE Steel Corporation of Japan, to build and operate a galvanized sheet steel plant in central Mexico. After delays caused by the COVID-19 pandemic, Nucor JFE is expected to begin commissioning in November of this year. Nucor accounts for its investment in Nucor-JFE (on a one-month lag basis) under the equity method, as control and risk of loss are shared equally between the members of Nucor-JFE. Nucor’s investment in Nucor-JFE was $150.3 million at October 3, 2020 ($163.2 million at December 31, 2019). On January 16, 2019, Nucor entered into an agreement to guarantee a percentage, equal to its ownership percentage (50%), of Nucor-JFE’s borrowings under the General Financing Agreement and Promissory Note (the “JFE Facility”). The fair value of the guarantee is immaterial. Nucor’s guarantee expires on April 30, 2021. The maximum amount Nucor-JFE could borrow under the JFE Facility was $65.0 million as of October 3, 2020. The JFE Facility is uncommitted. As of October 3, 2020, there was $45.0 million outstanding under the JFE Facility (none as of December 31, 2019). If Nucor-JFE fails to pay when due any amounts for which it is obligated under the JFE Facility, Nucor could be required to pay 50% of such amounts pursuant to and in accordance with the terms of its guarantee. Nucor has not recorded any liability associated with this guarantee. Nucor-JFE has other credit facilities that Nucor has agreed to guarantee. The principal amount subject to guarantee by Nucor for these other credit facilities was $25.0 million as of October 3, 2020 ($25.0 million as of December 31, 2019). The fair value of the guarantees is immaterial. If Nucor-JFE fails to pay when due any amounts for which it is obligated under the other credit facilities, Nucor could be required to pay such amounts pursuant to and in accordance with the terms of its guarantees. Nucor has not recorded any liability associated with these guarantees. All Equity Investments Nucor reviews its equity investments for impairment if and when circumstances indicate that a decline in fair value below their carrying amounts may have occurred. Nucor determined that a triggering event occurred in the first quarter of 2020 with respect to its equity method investment in Duferdofin Nucor due to adverse developments in the joint venture’s commercial outlook, which were and continue to be exacerbated by the COVID-19 pandemic, all of which have negatively impacted the joint venture’s strategic direction. After completing its impairment assessment, Nucor determined that the carrying amount exceeded its estimated fair value and the impairment condition was considered to be other than temporary. Therefore, Nucor recorded a $250.0 million impairment charge in the first quarter of 2020, a $5.0 million impairment charge in the second quarter of 2020, and a $6.6 million impairment charge in the third quarter of 2020 against its investment in Duferdofin Nucor. Any additional capital contributions, if necessary, that Nucor makes to Duferdofin Nucor will likely be subject to impairment. Additionally, in the first quarter of 2020 the Company fully reserved its €35.0 million ($41.0 million) outstanding note receivable from Duferdofin Nucor due to an assessment of the likelihood of collection in light of these adverse developments and its effective subordination to Facility A. These charges are included in losses on assets in the condensed consolidated statements of earnings. The assumptions that most significantly affect the fair value determination include projected cash flows and the discount rate. The Company-specific inputs for measuring fair value are considered “Level 3” or unobservable inputs that are not corroborated by market data under applicable fair value authoritative guidance, as quoted market prices are not available. It is reasonably possible that material deviation of future performance from the estimates used in our most recent valuation could result in further impairment of our investment in Duferdofin Nucor and affect any potential liability associated with the Company’s guarantee of the indebtedness of Duferdofin Nucor as discussed above.

Current Liabilities

Current Liabilities	9 Months Ended
	Oct. 03, 2020
Payables And Accruals [Abstract]
Current Liabilities	6. Current Liabilities Book overdrafts, included in accounts payable in the condensed consolidated balance sheets, were $115.2 million at October 3, 2020 ($116.4 million at December 31, 2019). Dividends payable, included in accrued expenses and other current liabilities in the condensed consolidated balance sheets, were $123.0 million at October 3, 2020 ($122.9 million at December 31, 2019).

Fair Value Measurements

Fair Value Measurements	9 Months Ended
	Oct. 03, 2020
Fair Value Disclosures [Abstract]
Fair Value Measurements	7. Fair Value Measurements The following table summarizes information regarding Nucor’s financial assets and financial liabilities that were measured at fair value as of October 3, 2020 and December 31, 2019 (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 October 3, 2020 Assets: Cash equivalents $ 2,539,777 $ 2,539,777 $ - $ - Short-term investments 412,401 412,401 - - Restricted cash and cash equivalents 131,623 131,623 Total assets $ 3,083,801 $ 3,083,801 $ - $ - Liabilities: Derivative contracts $ (6,577 ) $ - $ (6,577 ) $ - As of December 31, 2019 Assets: Cash equivalents $ 1,229,000 $ 1,229,000 $ - $ - Short-term investments 300,040 300,040 - - Total assets $ 1,529,040 $ 1,529,040 $ - $ - Liabilities: Derivative contracts $ (19,599 ) $ - $ (19,599 ) $ - 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 October 3, 2020 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. The fair value of short-term and long-term debt, including current maturities, was approximately $6.28 billion at October 3, 2020 ($4.81 billion at December 31, 2019). The debt fair value estimates are classified under Level 2 because such estimates are based on readily available market prices of our debt at October 3, 2020 and December 31, 2019, or similar debt with the same maturities, ratings and interest rates. Disclosures are required for certain assets and liabilities that are measured at fair value, but are recognized and disclosed on a nonrecurring basis in periods subsequent to initial recognition. For Nucor, our equity investment in Duferdofin Nucor was measured at fair value as a result of the impairment charges recorded in the first nine months of 2020 (see Note 5).

Contingencies

Contingencies	9 Months Ended
	Oct. 03, 2020
Commitments And Contingencies Disclosure [Abstract]
Contingencies	8. 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 $16.6 million of accrued environmental costs at October 3, 2020 ($16.4 million at December 31, 2019), $6.3 million was classified in accrued expenses and other current liabilities ($4.1 million at December 31, 2019) and $10.3 million was classified in deferred credits and other liabilities ($12.3 million at December 31, 2019). 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	9 Months Ended
	Oct. 03, 2020
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock-Based Compensation	9. 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 permits the award of stock options, restricted stock units, restricted shares and other stock-based awards for up to million shares of the Company’s common stock. As of October 3, 2020 , 7.8 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 October 3, 2020, 1.0 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 nine months of 2020 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 3,892 $ 50.78 Granted 529 $ 42.46 Exercised - $ - $ - Canceled (239 ) $ 51.58 Outstanding at October 3, 2020 4,182 $ 49.68 6.0 years $ 3,846 Stock options exercisable at October 3, 2020 3,435 $ 50.36 5.3 years $ 2,189 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 $0.3 million in the third quarter of both 2020 and 2019 and $2.4 million and $4.4 million in the first nine months of 2020 and 2019, respectively. As of October 3, 2020, unrecognized compensation expense related to stock options was $2.8 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 provided that a portion of the RSUs awarded to an officer prior to 2018 vest only upon the officer’s retirement. 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 nine months of 2020 is as follows (shares in thousands): Shares Grant Date Fair Value Restricted stock units: Unvested at beginning of year 1,776 $ 52.60 Granted 1,246 $ 42.46 Vested (1,140 ) $ 50.14 Canceled (22 ) $ 50.17 Unvested at October 3, 2020 1,860 $ 47.34 Compensation expense for RSUs was $11.1 million and $11.0 million in the third quarter of 2020 and 2019, respectively, and $47.9 million and $59.1 million in the first nine months of 2020 and 2019, respectively. As of October 3, 2020, unrecognized compensation expense related to unvested RSUs was $64.2 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 nine months of 2020 is as follows (shares in thousands): Grant Date Shares Fair Value Restricted stock units and restricted stock awards: Unvested at beginning of year 147 $ 60.81 Granted 348 $ 36.15 Vested (359 ) $ 40.98 Canceled - $ - Unvested at October 3, 2020 136 $ 49.98 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 $3.3 million and $1.8 million in the third quarter of 2020 and 2019, respectively, and $5.8 million and $10.9 million in the first nine months of 2020 and 2019, respectively. As of October 3, 2020, unrecognized compensation expense related to unvested restricted stock awards was $1.6 million, which is expected to be recognized over a weighted-average period of 1.6 years.

Employee Benefit Plan

Employee Benefit Plan	9 Months Ended
	Oct. 03, 2020
Compensation And Retirement Disclosure [Abstract]
Employee Benefit Plan	10. 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 $27.5 million and $40.0 million in the third quarter of 2020 and 2019, respectively, and $59.5 million and $163.7 million in the first nine months of 2020 and 2019, 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)	9 Months Ended
	Oct. 03, 2020
Banking And Thrift Interest [Abstract]
Interest Expense (Income)	11. Interest Expense (Income): The components of net interest expense for the third quarter and first nine months of 2020 and 2019 are as follows (in thousands): Three Months (13 Weeks) Ended Nine Months (39 Weeks) Ended Oct. 3, 2020 Sept. 28, 2019 Oct. 3, 2020 Sept. 28, 2019 Interest expense $ 42,281 $ 40,721 $ 128,726 $ 119,736 Interest income (2,142 ) (9,435 ) (11,870 ) (26,977 ) Interest expense, net $ 40,139 $ 31,286 $ 116,856 $ 92,759

Income Taxes

Income Taxes	9 Months Ended
	Oct. 03, 2020
Income Tax Disclosure [Abstract]
Income Taxes	12. Income Taxes The effective tax rate for the third quarter of 2020 was 23.3% as compared to 22.8% for the third quarter of 2019. Nucor has concluded U.S. federal income tax matters for years through 2016, other than 2015. 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 2013 through 2019 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 $575.2 million at October 3, 2020 ($431.0 million at December 31, 2019).

Stockholders' Equity

Stockholders' Equity	9 Months Ended
	Oct. 03, 2020
Equity [Abstract]
Stockholders' Equity	1 3. 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) of which Nucor owns 51%, for the three months and nine months ended October 3, 2020 and September 28, 2019 (in thousands): Three Months (13 Weeks) Ended October 3, 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, 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 Net earnings 222,630 - - - 193,415 - - - 193,415 29,215 Other comprehensive income (loss) 25,367 - - - - 25,367 - - 25,367 - Stock option expense 263 - - 263 - - - - 263 - Issuance of stock under award plans, net of forfeitures 11,189 - - 10,012 - - (34 ) 1,177 11,189 - Amortization of unearned compensation 400 - - 400 - - - - 400 - Cash dividends declared (123,039 ) - - - (123,039 ) - - - (123,039 ) - Distributions to noncontrolling interests (43,228 ) - - - - - - - - (43,228 ) Other - - - - (1 ) - - - (1 ) 1 BALANCES, October 3, 2020 $ 10,717,067 380,154 $ 152,061 $ 2,117,582 $ 11,068,908 $ (315,469 ) 78,225 $ (2,720,668 ) $ 10,302,414 $ 414,653 Nine Months (39 Weeks) Ended October 3, 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 410,162 - - - 322,627 - - - 322,627 87,535 Other comprehensive income (loss) (12,503 ) - - - - (12,503 ) - - (12,503 ) - Stock option expense 2,402 - - 2,402 - - - - 2,402 - Issuance of stock under award plans, net of forfeitures 38,996 - - 6,234 - - (942 ) 32,762 38,996 - Amortization of unearned compensation 1,300 - - 1,300 - - - - 1,300 - Treasury stock acquired (39,499 ) - - - - - 825 (39,499 ) (39,499 ) - Cash dividends declared (368,774 ) - - - (368,774 ) - - - (368,774 ) - Distributions to noncontrolling interests (106,193 ) - - - - - - - - (106,193 ) Other - - - - (1 ) - - - (1 ) 1 BALANCES, October 3, 2020 $ 10,717,067 380,154 $ 152,061 $ 2,117,582 $ 11,068,908 $ (315,469 ) 78,225 $ (2,720,668 ) $ 10,302,414 $ 414,653 Three Months (13 Weeks) Ended September 28, 2019 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, June 29, 2019 $ 10,698,008 380,154 $ 152,061 $ 2,098,809 $ 10,977,950 $ (297,760 ) 76,997 $ (2,630,343 ) $ 10,300,717 $ 397,291 Net earnings 293,587 - - - 275,031 - - - 275,031 18,556 Other comprehensive income (loss) (16,006 ) - - - - (16,006 ) - - (16,006 ) - Stock option expense 275 - - 275 - - - - 275 - Issuance of stock under award plans, net of forfeitures 11,339 - - 9,365 - - (58 ) 1,974 11,339 - Amortization of unearned compensation 500 - - 500 - - - - 500 - Cash dividends declared (122,809 ) - - - (122,809 ) - - - (122,809 ) - Distributions to noncontrolling interests (3,861 ) - - - - - - - - (3,861 ) Other - - - (1 ) - - - 1 - - BALANCES, September 28, 2019 $ 10,861,033 380,154 $ 152,061 $ 2,108,948 $ 11,130,172 $ (313,766 ) 76,939 $ (2,628,368 ) $ 10,449,047 $ 411,986 Nine Months (39 Weeks) Ended September 28, 2019 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, 2018 $ 10,201,968 380,154 $ 152,061 $ 2,073,715 $ 10,337,445 $ (304,133 ) 74,562 $ (2,467,010 ) $ 9,792,078 $ 409,890 Net earnings 1,236,657 - - - 1,163,320 - - - 1,163,320 73,337 Other comprehensive income (loss) (11,519 ) - - - - (11,519 ) - - (11,519 ) - Stock options exercised 5,892 - - 808 - - (153 ) 5,084 5,892 - Stock option expense 4,387 - - 4,387 - - - - 4,387 - Issuance of stock under award plans, net of forfeitures 59,608 - - 28,540 - - (920 ) 31,068 59,608 - Amortization of unearned compensation 1,500 - - 1,500 - - - - 1,500 - Treasury stock acquired (197,511 ) - - - - - 3,450 (197,511 ) (197,511 ) - Cash dividends declared (368,707 ) - - - (368,707 ) - - - (368,707 ) - Distributions to noncontrolling interests (71,241 ) - - - - - - - - (71,241 ) Other (1 ) - - (2 ) (1,886 ) 1,886 - 1 (1 ) - BALANCES, September 28, 2019 $ 10,861,033 380,154 $ 152,061 $ 2,108,948 $ 11,130,172 $ (313,766 ) 76,939 $ (2,628,368 ) $ 10,449,047 $ 411,986 Dividends declared per share were $0.4025 per share in the third quarter of 2020 ($0.40 per share in the third quarter of 2019) and $1.2075 per share in the first nine months of 2020 ($1.20 per share in the first nine months of 2019). On September 6, 2018, 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 $2.00 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 October 3, 2020, the Company had approximately $1.16 billion remaining available for share repurchases under the program.

Accumulated Other Comprehensive

Accumulated Other Comprehensive Income (Loss)	9 Months Ended
	Oct. 03, 2020
Equity [Abstract]
Accumulated Other Comprehensive Income (Loss)	14. Accumulated Other Comprehensive Income (Loss) The following tables reflect the changes in accumulated other comprehensive income (loss) by component for the three months and nine months ended October 3, 2020 and September 28, 2019 (in thousands): Three-Month (13-Week) Period Ended October 3, 2020 Gains and Losses on Foreign Currency Adjustment to Early Hedging Derivatives Gain (Loss) Retiree Medical Plan Total Accumulated other comprehensive income (loss) at July 4, 2020 $ (10,900 ) $ (337,743 ) $ 7,807 $ (340,836 ) Other comprehensive income (loss) before reclassifications 6,387 16,867 - 23,254 Amounts reclassified from accumulated other comprehensive income (loss) into earnings (1) 2,113 - - 2,113 Net current-period other comprehensive income (loss) 8,500 16,867 - 25,367 Accumulated other comprehensive income (loss) at October 3, 2020 $ (2,400 ) $ (320,876 ) $ 7,807 $ (315,469 ) Nine-Month (39-Week) Period Ended October 3, 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 4,888 (24,103 ) - (19,215 ) Amounts reclassified from accumulated other comprehensive income (loss) into earnings (1) 6,712 - - 6,712 Net current-period other comprehensive income (loss) 11,600 (24,103 ) - (12,503 ) Accumulated other comprehensive income (loss) at October 3, 2020 $ (2,400 ) $ (320,876 ) $ 7,807 $ (315,469 ) (1) Includes $2,113 and $6,712 of accumulated other comprehensive income (loss) reclassifications into cost of products sold for net losses on commodity contracts in the third quarter and first nine months of 2020, respectively. The tax impacts of those reclassifications were $700 and $2,300 in the third quarter and first nine months of 2020, respectively. Included in the $320.9 million foreign currency losses at October 3, 2020 are $191.5 million of losses related to our equity method investment in Duferdofin Nucor and $129.4 million of losses related primarily to our Canadian operations. Three-Month (13-Week) Period Ended September 28, 2019 Gains and Losses on Foreign Currency Adjustment to Early Hedging Derivatives Gain (Loss) Retiree Medical Plan Total Accumulated other comprehensive income (loss) at June 29, 2019 $ (11,100 ) $ (295,559 ) $ 8,899 $ (297,760 ) Other comprehensive income (loss) before reclassifications (3,315 ) (14,306 ) - (17,621 ) Amounts reclassified from accumulated other comprehensive income (loss) into earnings (1) 1,615 - - 1,615 Net current-period other comprehensive income (loss) (1,700 ) (14,306 ) - (16,006 ) Accumulated other comprehensive income (loss) at September 28, 2019 $ (12,800 ) $ (309,865 ) $ 8,899 $ (313,766 ) Nine-Month (39-Week) Period Ended September 28, 2019 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, 2018 $ (6,500 ) $ (304,646 ) $ 7,013 $ (304,133 ) Other comprehensive income (loss) before reclassifications (7,801 ) (5,219 ) - (13,020 ) Amounts reclassified from accumulated other comprehensive income (loss) into earnings (1) 1,501 - - 1,501 Net current-period other comprehensive income (loss) (6,300 ) (5,219 ) - (11,519 ) Other - - 1,886 1,886 Accumulated other comprehensive income (loss) at September 28, 2019 $ (12,800 ) $ (309,865 ) $ 8,899 $ (313,766 ) (1) Includes $1,615 and $1,501 of accumulated other comprehensive income (loss) reclassifications into cost of products sold for net losses on commodity contracts in the third quarter and first nine months of 2019, respectively. The tax impacts of those reclassifications were $500 in both the third quarter and first nine months of 2019.

Segments

Segments	9 Months Ended
	Oct. 03, 2020
Segment Reporting [Abstract]
Segments	15. 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 Duferdofin Nucor, NuMit and 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 (collectively, “DJJ”), primarily a scrap broker and processor; Nu-Iron Unlimited and Nucor Steel Louisiana LLC, 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, allowances to eliminate intercompany profit in inventory, deferred income tax assets, federal and state income taxes receivable and investment in and advances to affiliates. Nucor’s results by segment for the third quarter and first nine months of 2020 and 2019 were as follows (in thousands): Three Months (13 Weeks) Ended Nine Months (39 Weeks) Ended Oct. 3, 2020 Sept. 28, 2019 Oct. 3, 2020 Sept. 28, 2019 Net sales to external customers: Steel mills $ 2,842,625 $ 3,244,473 $ 8,875,856 $ 10,897,322 Steel products 1,738,004 1,820,359 4,988,026 5,225,064 Raw materials 347,331 399,670 1,015,721 1,334,726 $ 4,927,960 $ 5,464,502 $ 14,879,603 $ 17,457,112 Intercompany sales: Steel mills $ 731,942 $ 825,237 $ 2,264,278 $ 2,542,008 Steel products 51,029 57,517 197,603 174,718 Raw materials 1,863,796 2,063,167 5,772,583 6,917,523 Corporate/eliminations (2,646,767) (2,945,921 ) (8,234,464) (9,634,249 ) $ - $ - $ - $ - Earnings (loss) before income taxes and noncontrolling interests: Steel mills $ 205,152 $ 309,939 $ 512,082 $ 1,578,257 Steel products 186,976 170,214 502,409 363,731 Raw materials 6,232 (10,599 ) (3,068) 64,333 Corporate/eliminations (107,942) (89,215 ) (393,651) (401,744 ) $ 290,418 $ 380,339 $ 617,772 $ 1,604,577 Oct. 3, 2020 Dec. 31, 2019 Segment assets: Steel mills $ 9,251,790 $ 9,283,216 Steel products 4,399,501 4,610,628 Raw materials 3,172,464 3,316,479 Corporate/eliminations 2,695,522 1,134,343 $ 19,519,277 $ 18,344,666

Revenue

Revenue	9 Months Ended
	Oct. 03, 2020
Revenue From Contract With Customer [Abstract]
Revenue	16. Revenue The following tables disaggregate our revenue by major source for the third quarter and first nine months of 2020 and 2019 (in thousands): Three Months (13 Weeks) Ended October 3, 2020 Nine Months (39 Weeks) Ended October 3, 2020 Steel Mills Steel Products Raw Materials Total Steel Mills Steel Products Raw Materials Total Sheet $ 1,256,537 $ - $ - $ 1,256,537 $ 3,899,970 $ - $ - $ 3,899,970 Bar 957,216 - - 957,216 2,830,936 - - 2,830,936 Structural 362,192 - - 362,192 1,159,949 - - 1,159,949 Plate 266,680 - - 266,680 985,001 - - 985,001 Tubular Products - 274,915 - 274,915 - 830,283 - 830,283 Rebar Fabrication - 463,286 - 463,286 - 1,300,518 - 1,300,518 Other Steel Products - 999,803 - 999,803 - 2,857,225 - 2,857,225 Raw Materials - - 347,331 347,331 - - 1,015,721 1,015,721 $ 2,842,625 $ 1,738,004 $ 347,331 $ 4,927,960 $ 8,875,856 $ 4,988,026 $ 1,015,721 $ 14,879,603 Three Months (13 Weeks) Ended September 28, 2019 Nine Months (39 Weeks) Ended September 28, 2019 Steel Mills Steel Products Raw Materials Total Steel Mills Steel Products Raw Materials Total Sheet $ 1,513,884 $ - $ - $ 1,513,884 $ 5,071,027 $ - $ - $ 5,071,027 Bar 979,082 - - 979,082 3,173,289 - - 3,173,289 Structural 378,670 - - 378,670 1,214,355 - - 1,214,355 Plate 372,837 - - 372,837 1,438,651 - - 1,438,651 Tubular Products - 296,519 - 296,519 - 919,711 - 919,711 Rebar Fabrication - 469,180 - 469,180 - 1,249,912 - 1,249,912 Other Steel Products - 1,054,660 - 1,054,660 - 3,055,441 - 3,055,441 Raw Materials - - 399,670 399,670 - - 1,334,726 1,334,726 $ 3,244,473 $ 1,820,359 $ 399,670 $ 5,464,502 $ 10,897,322 $ 5,225,064 $ 1,334,726 $ 17,457,112 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 $114.3 million as of October 3, 2020 ($108.6 million as of December 31, 2019), and are included in accrued expenses and other current liabilities in the condensed consolidated balance sheets.

Earnings Per Share

Earnings Per Share	9 Months Ended
	Oct. 03, 2020
Earnings Per Share [Abstract]
Earnings Per Share	17. Earnings Per Share The computations of basic and diluted net earnings per share for the third quarter and first nine months of 2020 and 2019 are as follows (in thousands, except per share amounts): Three Months (13 Weeks) Ended Nine Months (39 Weeks) Ended Oct. 3, 2020 Sept. 28, 2019 Oct. 3, 2020 Sept. 28, 2019 Basic net earnings per share: Basic net earnings $ 193,415 $ 275,031 $ 322,627 $ 1,163,320 Earnings allocated to participating securities (1,201 ) (1,655 ) (2,182 ) (6,295 ) Net earnings available to common stockholders $ 192,214 $ 273,376 $ 320,445 $ 1,157,025 Basic average shares outstanding 303,394 304,637 303,072 305,553 Basic net earnings per share $ 0.63 $ 0.90 $ 1.06 $ 3.79 Diluted net earnings per share: Diluted net earnings $ 193,415 $ 275,031 $ 322,627 $ 1,163,320 Earnings allocated to participating securities (1,202 ) (1,656 ) (2,182 ) (6,295 ) Net earnings available to common stockholders $ 192,213 $ 273,375 $ 320,445 $ 1,157,025 Diluted average shares outstanding: Basic average shares outstanding 303,394 304,637 303,072 305,553 Dilutive effect of stock options and other 47 343 27 476 303,441 304,980 303,099 306,029 Diluted net earnings per share $ 0.63 $ 0.90 $ 1.06 $ 3.78 The following stock options were excluded from the computation of diluted net earnings per share for the third quarter and first nine months of 2020 and 2019 because their effect would have been anti-dilutive (shares in thousands): Three Months (13 Weeks) Ended Nine Months (39 Weeks) Ended Oct. 3, 2020 Sept. 28, 2019 Oct. 3, 2020 Sept. 28, 2019 Anti-dilutive stock options: Weighted-average shares 3,463 963 3,638 963 Weighted-average exercise price $ 51.38 $ 60.92 $ 51.15 $ 60.92

Restricted Cash and Cash Equiva

Restricted Cash and Cash Equivalents	9 Months Ended
	Oct. 03, 2020
Restricted Cash And Cash Equivalents [Abstract]
Restricted Cash and Cash Equivalents	1 8 . R e stricted Cash and Cash Equivalents As of October 3, 2020, restricted cash and cash equivalents totaled $131.6 million, and primarily consisted of net proceeds from the issuance of $162.6 million in 40-year variable-rate Green Bonds in July 2020. The restricted cash and cash equivalents are held in a trust account and are to be used to partially fund the capital costs, in particular the expenditures associated with pollution prevention and control including waste recycling, associated with the construction of Nucor’s plate mill located in Brandenburg, Kentucky. Funds are disbursed from the trust account as qualified expenditures for the construction of the Brandenburg facility are made ($31.0 million in the third quarter of 2020). Interest earned on funds held in the trust account is subject to the same usage requirements as the bond proceeds principle. Since the restricted cash and interest and dividends must be used for the construction of the Brandenburg facility and relate to a long-term liability, the entire balance has been classified as a non-current asset.

Debt

Debt	9 Months Ended
	Oct. 03, 2020
Debt Disclosure [Abstract]
Debt	19. Debt In May 2020, Nucor issued $500.0 million of 2.000% Notes due 2025 and $500.0 million of 2.700% Notes due 2030. Net proceeds of the issuances were $989.4 million. Costs of $8.4 million associated with the issuances have been capitalized and will be amortized over the life of the notes. In July 2020 162.6 40

Subsequent Event

Subsequent Event	9 Months Ended
	Oct. 03, 2020
Subsequent Events [Abstract]
Subsequent Event	20. Subsequent Event Subsequent to the end of the third quarter of 2020, we received certification of state income tax credits that will result in an approximately $40 million net benefit to our provision for income taxes in the fourth quarter of 2020.

Goodwill and Other Intangible_2

Goodwill and Other Intangible Assets (Tables)	9 Months Ended
	Oct. 03, 2020
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 nine months ended October 3, 2020 by segment was as follows (in thousands): Steel Mills Steel Products Raw Materials Total Balance at December 31, 2019 $ 591,986 $ 879,500 $ 729,577 $ 2,201,063 Other - (821 ) - (821 ) Translation - (4,454 ) - (4,454 ) Balance at October 3, 2020 $ 591,986 $ 874,225 $ 729,577 $ 2,195,788
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 October 3, 2020 and December 31, 2019 (in thousands): October 3, 2020 December 31, 2019 Gross Amount Accumulated Amortization Gross Amount Accumulated Amortization Customer relationships $ 1,412,323 $ 821,029 $ 1,412,954 $ 767,532 Trademarks and trade names 162,062 98,110 162,183 92,258 Other 63,822 40,510 63,807 36,968 $ 1,638,207 $ 959,649 $ 1,638,944 $ 896,758

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	9 Months Ended
	Oct. 03, 2020
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 October 3, 2020 and December 31, 2019 (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 October 3, 2020 Assets: Cash equivalents $ 2,539,777 $ 2,539,777 $ - $ - Short-term investments 412,401 412,401 - - Restricted cash and cash equivalents 131,623 131,623 Total assets $ 3,083,801 $ 3,083,801 $ - $ - Liabilities: Derivative contracts $ (6,577 ) $ - $ (6,577 ) $ - As of December 31, 2019 Assets: Cash equivalents $ 1,229,000 $ 1,229,000 $ - $ - Short-term investments 300,040 300,040 - - Total assets $ 1,529,040 $ 1,529,040 $ - $ - Liabilities: Derivative contracts $ (19,599 ) $ - $ (19,599 ) $ -

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	9 Months Ended
	Oct. 03, 2020
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 nine months of 2020 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 3,892 $ 50.78 Granted 529 $ 42.46 Exercised - $ - $ - Canceled (239 ) $ 51.58 Outstanding at October 3, 2020 4,182 $ 49.68 6.0 years $ 3,846 Stock options exercisable at October 3, 2020 3,435 $ 50.36 5.3 years $ 2,189
Summary of Nucor's RSU Activity	A summary of Nucor’s RSU activity for the first nine months of 2020 is as follows (shares in thousands): Shares Grant Date Fair Value Restricted stock units: Unvested at beginning of year 1,776 $ 52.60 Granted 1,246 $ 42.46 Vested (1,140 ) $ 50.14 Canceled (22 ) $ 50.17 Unvested at October 3, 2020 1,860 $ 47.34
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 nine months of 2020 is as follows (shares in thousands): Grant Date Shares Fair Value Restricted stock units and restricted stock awards: Unvested at beginning of year 147 $ 60.81 Granted 348 $ 36.15 Vested (359 ) $ 40.98 Canceled - $ - Unvested at October 3, 2020 136 $ 49.98

Interest Expense (Income) (Tabl

Interest Expense (Income) (Tables)	9 Months Ended
	Oct. 03, 2020
Banking And Thrift Interest [Abstract]
Schedule of Components of Net Interest Expense	The components of net interest expense for the third quarter and first nine months of 2020 and 2019 are as follows (in thousands): Three Months (13 Weeks) Ended Nine Months (39 Weeks) Ended Oct. 3, 2020 Sept. 28, 2019 Oct. 3, 2020 Sept. 28, 2019 Interest expense $ 42,281 $ 40,721 $ 128,726 $ 119,736 Interest income (2,142 ) (9,435 ) (11,870 ) (26,977 ) Interest expense, net $ 40,139 $ 31,286 $ 116,856 $ 92,759

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	9 Months Ended
	Oct. 03, 2020
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) of which Nucor owns 51%, for the three months and nine months ended October 3, 2020 and September 28, 2019 (in thousands): Three Months (13 Weeks) Ended October 3, 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, 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 Net earnings 222,630 - - - 193,415 - - - 193,415 29,215 Other comprehensive income (loss) 25,367 - - - - 25,367 - - 25,367 - Stock option expense 263 - - 263 - - - - 263 - Issuance of stock under award plans, net of forfeitures 11,189 - - 10,012 - - (34 ) 1,177 11,189 - Amortization of unearned compensation 400 - - 400 - - - - 400 - Cash dividends declared (123,039 ) - - - (123,039 ) - - - (123,039 ) - Distributions to noncontrolling interests (43,228 ) - - - - - - - - (43,228 ) Other - - - - (1 ) - - - (1 ) 1 BALANCES, October 3, 2020 $ 10,717,067 380,154 $ 152,061 $ 2,117,582 $ 11,068,908 $ (315,469 ) 78,225 $ (2,720,668 ) $ 10,302,414 $ 414,653 Nine Months (39 Weeks) Ended October 3, 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 410,162 - - - 322,627 - - - 322,627 87,535 Other comprehensive income (loss) (12,503 ) - - - - (12,503 ) - - (12,503 ) - Stock option expense 2,402 - - 2,402 - - - - 2,402 - Issuance of stock under award plans, net of forfeitures 38,996 - - 6,234 - - (942 ) 32,762 38,996 - Amortization of unearned compensation 1,300 - - 1,300 - - - - 1,300 - Treasury stock acquired (39,499 ) - - - - - 825 (39,499 ) (39,499 ) - Cash dividends declared (368,774 ) - - - (368,774 ) - - - (368,774 ) - Distributions to noncontrolling interests (106,193 ) - - - - - - - - (106,193 ) Other - - - - (1 ) - - - (1 ) 1 BALANCES, October 3, 2020 $ 10,717,067 380,154 $ 152,061 $ 2,117,582 $ 11,068,908 $ (315,469 ) 78,225 $ (2,720,668 ) $ 10,302,414 $ 414,653 Three Months (13 Weeks) Ended September 28, 2019 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, June 29, 2019 $ 10,698,008 380,154 $ 152,061 $ 2,098,809 $ 10,977,950 $ (297,760 ) 76,997 $ (2,630,343 ) $ 10,300,717 $ 397,291 Net earnings 293,587 - - - 275,031 - - - 275,031 18,556 Other comprehensive income (loss) (16,006 ) - - - - (16,006 ) - - (16,006 ) - Stock option expense 275 - - 275 - - - - 275 - Issuance of stock under award plans, net of forfeitures 11,339 - - 9,365 - - (58 ) 1,974 11,339 - Amortization of unearned compensation 500 - - 500 - - - - 500 - Cash dividends declared (122,809 ) - - - (122,809 ) - - - (122,809 ) - Distributions to noncontrolling interests (3,861 ) - - - - - - - - (3,861 ) Other - - - (1 ) - - - 1 - - BALANCES, September 28, 2019 $ 10,861,033 380,154 $ 152,061 $ 2,108,948 $ 11,130,172 $ (313,766 ) 76,939 $ (2,628,368 ) $ 10,449,047 $ 411,986 Nine Months (39 Weeks) Ended September 28, 2019 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, 2018 $ 10,201,968 380,154 $ 152,061 $ 2,073,715 $ 10,337,445 $ (304,133 ) 74,562 $ (2,467,010 ) $ 9,792,078 $ 409,890 Net earnings 1,236,657 - - - 1,163,320 - - - 1,163,320 73,337 Other comprehensive income (loss) (11,519 ) - - - - (11,519 ) - - (11,519 ) - Stock options exercised 5,892 - - 808 - - (153 ) 5,084 5,892 - Stock option expense 4,387 - - 4,387 - - - - 4,387 - Issuance of stock under award plans, net of forfeitures 59,608 - - 28,540 - - (920 ) 31,068 59,608 - Amortization of unearned compensation 1,500 - - 1,500 - - - - 1,500 - Treasury stock acquired (197,511 ) - - - - - 3,450 (197,511 ) (197,511 ) - Cash dividends declared (368,707 ) - - - (368,707 ) - - - (368,707 ) - Distributions to noncontrolling interests (71,241 ) - - - - - - - - (71,241 ) Other (1 ) - - (2 ) (1,886 ) 1,886 - 1 (1 ) - BALANCES, September 28, 2019 $ 10,861,033 380,154 $ 152,061 $ 2,108,948 $ 11,130,172 $ (313,766 ) 76,939 $ (2,628,368 ) $ 10,449,047 $ 411,986

Accumulated Other Comprehensi_2

Accumulated Other Comprehensive Income (Loss) (Tables)	9 Months Ended
	Oct. 03, 2020
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 nine months ended October 3, 2020 and September 28, 2019 (in thousands): Three-Month (13-Week) Period Ended October 3, 2020 Gains and Losses on Foreign Currency Adjustment to Early Hedging Derivatives Gain (Loss) Retiree Medical Plan Total Accumulated other comprehensive income (loss) at July 4, 2020 $ (10,900 ) $ (337,743 ) $ 7,807 $ (340,836 ) Other comprehensive income (loss) before reclassifications 6,387 16,867 - 23,254 Amounts reclassified from accumulated other comprehensive income (loss) into earnings (1) 2,113 - - 2,113 Net current-period other comprehensive income (loss) 8,500 16,867 - 25,367 Accumulated other comprehensive income (loss) at October 3, 2020 $ (2,400 ) $ (320,876 ) $ 7,807 $ (315,469 ) Nine-Month (39-Week) Period Ended October 3, 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 4,888 (24,103 ) - (19,215 ) Amounts reclassified from accumulated other comprehensive income (loss) into earnings (1) 6,712 - - 6,712 Net current-period other comprehensive income (loss) 11,600 (24,103 ) - (12,503 ) Accumulated other comprehensive income (loss) at October 3, 2020 $ (2,400 ) $ (320,876 ) $ 7,807 $ (315,469 ) (1) Includes $2,113 and $6,712 of accumulated other comprehensive income (loss) reclassifications into cost of products sold for net losses on commodity contracts in the third quarter and first nine months of 2020, respectively. The tax impacts of those reclassifications were $700 and $2,300 in the third quarter and first nine months of 2020, respectively. Included in the $320.9 million foreign currency losses at October 3, 2020 are $191.5 million of losses related to our equity method investment in Duferdofin Nucor and $129.4 million of losses related primarily to our Canadian operations. Three-Month (13-Week) Period Ended September 28, 2019 Gains and Losses on Foreign Currency Adjustment to Early Hedging Derivatives Gain (Loss) Retiree Medical Plan Total Accumulated other comprehensive income (loss) at June 29, 2019 $ (11,100 ) $ (295,559 ) $ 8,899 $ (297,760 ) Other comprehensive income (loss) before reclassifications (3,315 ) (14,306 ) - (17,621 ) Amounts reclassified from accumulated other comprehensive income (loss) into earnings (1) 1,615 - - 1,615 Net current-period other comprehensive income (loss) (1,700 ) (14,306 ) - (16,006 ) Accumulated other comprehensive income (loss) at September 28, 2019 $ (12,800 ) $ (309,865 ) $ 8,899 $ (313,766 ) Nine-Month (39-Week) Period Ended September 28, 2019 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, 2018 $ (6,500 ) $ (304,646 ) $ 7,013 $ (304,133 ) Other comprehensive income (loss) before reclassifications (7,801 ) (5,219 ) - (13,020 ) Amounts reclassified from accumulated other comprehensive income (loss) into earnings (1) 1,501 - - 1,501 Net current-period other comprehensive income (loss) (6,300 ) (5,219 ) - (11,519 ) Other - - 1,886 1,886 Accumulated other comprehensive income (loss) at September 28, 2019 $ (12,800 ) $ (309,865 ) $ 8,899 $ (313,766 ) (1) Includes $1,615 and $1,501 of accumulated other comprehensive income (loss) reclassifications into cost of products sold for net losses on commodity contracts in the third quarter and first nine months of 2019, respectively. The tax impacts of those reclassifications were $500 in both the third quarter and first nine months of 2019.

Segments (Tables)

Segments (Tables)	9 Months Ended
	Oct. 03, 2020
Segment Reporting [Abstract]
Segments	Nucor’s results by segment for the third quarter and first nine months of 2020 and 2019 were as follows (in thousands): Three Months (13 Weeks) Ended Nine Months (39 Weeks) Ended Oct. 3, 2020 Sept. 28, 2019 Oct. 3, 2020 Sept. 28, 2019 Net sales to external customers: Steel mills $ 2,842,625 $ 3,244,473 $ 8,875,856 $ 10,897,322 Steel products 1,738,004 1,820,359 4,988,026 5,225,064 Raw materials 347,331 399,670 1,015,721 1,334,726 $ 4,927,960 $ 5,464,502 $ 14,879,603 $ 17,457,112 Intercompany sales: Steel mills $ 731,942 $ 825,237 $ 2,264,278 $ 2,542,008 Steel products 51,029 57,517 197,603 174,718 Raw materials 1,863,796 2,063,167 5,772,583 6,917,523 Corporate/eliminations (2,646,767) (2,945,921 ) (8,234,464) (9,634,249 ) $ - $ - $ - $ - Earnings (loss) before income taxes and noncontrolling interests: Steel mills $ 205,152 $ 309,939 $ 512,082 $ 1,578,257 Steel products 186,976 170,214 502,409 363,731 Raw materials 6,232 (10,599 ) (3,068) 64,333 Corporate/eliminations (107,942) (89,215 ) (393,651) (401,744 ) $ 290,418 $ 380,339 $ 617,772 $ 1,604,577 Oct. 3, 2020 Dec. 31, 2019 Segment assets: Steel mills $ 9,251,790 $ 9,283,216 Steel products 4,399,501 4,610,628 Raw materials 3,172,464 3,316,479 Corporate/eliminations 2,695,522 1,134,343 $ 19,519,277 $ 18,344,666

Revenue (Tables)

Revenue (Tables)	9 Months Ended
	Oct. 03, 2020
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 third quarter and first nine months of 2020 and 2019 (in thousands): Three Months (13 Weeks) Ended October 3, 2020 Nine Months (39 Weeks) Ended October 3, 2020 Steel Mills Steel Products Raw Materials Total Steel Mills Steel Products Raw Materials Total Sheet $ 1,256,537 $ - $ - $ 1,256,537 $ 3,899,970 $ - $ - $ 3,899,970 Bar 957,216 - - 957,216 2,830,936 - - 2,830,936 Structural 362,192 - - 362,192 1,159,949 - - 1,159,949 Plate 266,680 - - 266,680 985,001 - - 985,001 Tubular Products - 274,915 - 274,915 - 830,283 - 830,283 Rebar Fabrication - 463,286 - 463,286 - 1,300,518 - 1,300,518 Other Steel Products - 999,803 - 999,803 - 2,857,225 - 2,857,225 Raw Materials - - 347,331 347,331 - - 1,015,721 1,015,721 $ 2,842,625 $ 1,738,004 $ 347,331 $ 4,927,960 $ 8,875,856 $ 4,988,026 $ 1,015,721 $ 14,879,603 Three Months (13 Weeks) Ended September 28, 2019 Nine Months (39 Weeks) Ended September 28, 2019 Steel Mills Steel Products Raw Materials Total Steel Mills Steel Products Raw Materials Total Sheet $ 1,513,884 $ - $ - $ 1,513,884 $ 5,071,027 $ - $ - $ 5,071,027 Bar 979,082 - - 979,082 3,173,289 - - 3,173,289 Structural 378,670 - - 378,670 1,214,355 - - 1,214,355 Plate 372,837 - - 372,837 1,438,651 - - 1,438,651 Tubular Products - 296,519 - 296,519 - 919,711 - 919,711 Rebar Fabrication - 469,180 - 469,180 - 1,249,912 - 1,249,912 Other Steel Products - 1,054,660 - 1,054,660 - 3,055,441 - 3,055,441 Raw Materials - - 399,670 399,670 - - 1,334,726 1,334,726 $ 3,244,473 $ 1,820,359 $ 399,670 $ 5,464,502 $ 10,897,322 $ 5,225,064 $ 1,334,726 $ 17,457,112

Earnings Per Share (Tables)

Earnings Per Share (Tables)	9 Months Ended
	Oct. 03, 2020
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 third quarter and first nine months of 2020 and 2019 are as follows (in thousands, except per share amounts): Three Months (13 Weeks) Ended Nine Months (39 Weeks) Ended Oct. 3, 2020 Sept. 28, 2019 Oct. 3, 2020 Sept. 28, 2019 Basic net earnings per share: Basic net earnings $ 193,415 $ 275,031 $ 322,627 $ 1,163,320 Earnings allocated to participating securities (1,201 ) (1,655 ) (2,182 ) (6,295 ) Net earnings available to common stockholders $ 192,214 $ 273,376 $ 320,445 $ 1,157,025 Basic average shares outstanding 303,394 304,637 303,072 305,553 Basic net earnings per share $ 0.63 $ 0.90 $ 1.06 $ 3.79 Diluted net earnings per share: Diluted net earnings $ 193,415 $ 275,031 $ 322,627 $ 1,163,320 Earnings allocated to participating securities (1,202 ) (1,656 ) (2,182 ) (6,295 ) Net earnings available to common stockholders $ 192,213 $ 273,375 $ 320,445 $ 1,157,025 Diluted average shares outstanding: Basic average shares outstanding 303,394 304,637 303,072 305,553 Dilutive effect of stock options and other 47 343 27 476 303,441 304,980 303,099 306,029 Diluted net earnings per share $ 0.63 $ 0.90 $ 1.06 $ 3.78
Anti-dilutive Stock Options	The following stock options were excluded from the computation of diluted net earnings per share for the third quarter and first nine months of 2020 and 2019 because their effect would have been anti-dilutive (shares in thousands): Three Months (13 Weeks) Ended Nine Months (39 Weeks) Ended Oct. 3, 2020 Sept. 28, 2019 Oct. 3, 2020 Sept. 28, 2019 Anti-dilutive stock options: Weighted-average shares 3,463 963 3,638 963 Weighted-average exercise price $ 51.38 $ 60.92 $ 51.15 $ 60.92

Inventories - Additional Inform

Inventories - Additional Information (Detail)	Oct. 03, 2020	Dec. 31, 2019
Inventory Disclosure [Abstract]
Raw materials and supplies in inventory, percentage	40.00%	42.00%
Finished and semi-finished products in inventory, percentage	60.00%	58.00%

Property, Plant and Equipment -

Property, Plant and Equipment - Additional Information (Detail) $ in Thousands	3 Months Ended
	Dec. 31, 2019USD ($)	Oct. 03, 2020USD ($)a
Property, Plant and Equipment [Line Items]
Accumulated depreciation	$ 9,420,000	$ 9,870,000
Property, plant and equipment, net	6,178,555	6,829,733
Carrying Value of One Field of Wells [Member]
Property, Plant and Equipment [Line Items]
Non-cash impairment charge	35,000
Property, plant and equipment, net	12,300	11,200
Carrying Value of Two Field of Wells [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, net	$ 66,600	62,400
Unproved Oil and Natural Gas Properties [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, net		$ 165,000
Ownership percentage of leasehold interest in unproved oil and natural gas properties		49.00%
Unproved oil and gas properties area | a		54,000

Goodwill and Other Intangible_3

Goodwill and Other Intangible Assets - Schedule of Change in Net Carrying Amount of Goodwill by Segment (Detail) $ in Thousands	9 Months Ended
	Oct. 03, 2020USD ($)
Goodwill [Line Items]
Balance, beginning of period	$ 2,201,063
Other	(821)
Translation	(4,454)
Balance, end of period	2,195,788
Steel Mills [Member]
Goodwill [Line Items]
Balance, beginning of period	591,986
Balance, end of period	591,986
Steel Products [Member]
Goodwill [Line Items]
Balance, beginning of period	879,500
Other	(821)
Translation	(4,454)
Balance, end of period	874,225
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			9 Months Ended
	Oct. 03, 2020	Dec. 31, 2019	Sep. 28, 2019	Oct. 03, 2020	Sep. 28, 2019
Finite And Indefinite Lived Intangible Assets [Line Items]
Impairment of goodwill		$ 0
Goodwill	$ 2,195,788,000	2,201,063,000		$ 2,195,788,000
Finite-lived intangible assets	678,558,000	$ 742,186,000		678,558,000
Intangible asset amortization expense	20,700,000		$ 22,000,000	62,900,000	$ 64,700,000
Future amortization expense, in 2020	83,500,000			83,500,000
Future amortization expense, in 2021	82,300,000			82,300,000
Future amortization expense, in 2022	80,700,000			80,700,000
Future amortization expense, in 2023	80,000,000			80,000,000
Future amortization expense, in 2024	79,200,000			$ 79,200,000
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		56.00%
Goodwill	352,700,000	$ 356,600,000		$ 352,700,000
Finite-lived intangible assets	59,600,000	67,200,000		59,600,000
Grating unit [Member]
Finite And Indefinite Lived Intangible Assets [Line Items]
Percentage of fair value exceeded carrying value			17.00%
Goodwill	$ 36,600,000	$ 36,800,000		$ 36,600,000

Goodwill and Other Intangible_5

Goodwill and Other Intangible Assets - Schedule of Intangible Assets (Detail) - USD ($) $ in Thousands	Oct. 03, 2020	Dec. 31, 2019
Finite-Lived Intangible Assets [Line Items]
Intangible assets, Gross Amount	$ 1,638,207	$ 1,638,944
Intangible assets, Accumulated Amortization	959,649	896,758
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, Gross Amount	1,412,323	1,412,954
Intangible assets, Accumulated Amortization	821,029	767,532
Trademarks and Trade Names [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, Gross Amount	162,062	162,183
Intangible assets, Accumulated Amortization	98,110	92,258
Other [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, Gross Amount	63,822	63,807
Intangible assets, Accumulated Amortization	$ 40,510	$ 36,968

Equity Investments - Additional

Equity Investments - Additional Information (Detail) € in Millions	3 Months Ended				9 Months Ended		12 Months Ended
	Oct. 03, 2020USD ($)	Jul. 04, 2020USD ($)	Apr. 04, 2020USD ($)	Sep. 28, 2019USD ($)	Oct. 03, 2020USD ($)Sheet	Sep. 28, 2019USD ($)	Dec. 31, 2019USD ($)	Oct. 03, 2020EUR (€)	Oct. 02, 2020	Apr. 04, 2020EUR (€)	Dec. 31, 2019EUR (€)	Jan. 16, 2019
Schedule Of Equity Method Investments [Line Items]
Equity method investments	$ 521,200,000				$ 521,200,000		$ 793,200,000
Amortization					62,877,000	$ 64,655,000
NuMit LLC [Member]
Schedule Of Equity Method Investments [Line Items]
Equity method investments	$ 322,500,000				$ 322,500,000		319,800,000
Equity method investment, ownership percentage	50.00%				50.00%			50.00%
Period used for lag basis, in months					1 month
Distributions from affiliates					$ 2,000,000	27,400,000
Steel Technologies LLC [Member]
Schedule Of Equity Method Investments [Line Items]
Equity method investment, ownership percentage	100.00%				100.00%			100.00%
Number of sheet processing facilities operated by Steel Technologies | Sheet					26
Duferdofin Nucor S.r.l. [Member]
Schedule Of Equity Method Investments [Line Items]
Equity method investments	$ 100,000				$ 100,000		263,000,000
Equity method investment, ownership percentage	50.00%				50.00%			50.00%	50.00%
Period used for lag basis, in months					1 month
Equity method investments, share of net assets	$ 128,600,000				$ 128,600,000
Equity method investments impairment charges	6,600,000	$ 5,000,000	$ 250,000,000		261,600,000
Basis difference due to the step-up to fair value of certain assets and liabilities	(128,500,000)				(128,500,000)
Step-up to fair value of equity method investment, portion related to identification of goodwill							86,500,000
Amortization	(1,900,000)			$ 2,200,000	(1,600,000)	$ 6,700,000
Due from related parties, noncurrent	41,000,000				$ 41,000,000		39,300,000	€ 35			€ 35
Interest rate per year in excess of Euribor as of date of the notes					0.75%
Equity method investments notes payable with parent company, maturity date					Jan. 31, 2022
Equity method investment, remaining ownership percentage									50.00%
Due from related parties			$ 41,000,000							€ 35
Duferdofin Nucor S.r.l. [Member] | Facility A [Member]
Schedule Of Equity Method Investments [Line Items]
Equity method investments credit facilities subject to guarantee, amount	187,500,000				$ 187,500,000			160
Total amount outstanding under equity method investments credit facilities	$ 154,700,000				$ 154,700,000		164,900,000	€ 132			€ 147
Guarantor obligation percentage of exposure in case of default	50.00%				50.00%			50.00%
Line of credit facility, maturity period					Apr. 16, 2021
Nucor-JFE [Member]
Schedule Of Equity Method Investments [Line Items]
Equity method investments	$ 150,300,000				$ 150,300,000		163,200,000
Equity method investment, ownership percentage	50.00%				50.00%			50.00%				50.00%
Principal amount subject to guarantee for other credit facilities	$ 25,000,000				$ 25,000,000		25,000,000
Nucor-JFE [Member] | General Financing Agreement and Promissory Note [Member]
Schedule Of Equity Method Investments [Line Items]
Equity method investments credit facilities subject to guarantee, amount	65,000,000				65,000,000
Total amount outstanding under equity method investments credit facilities	$ 45,000,000				$ 45,000,000		$ 0
Guarantor obligation percentage of exposure in case of default	50.00%				50.00%			50.00%

Current Liabilities - Additiona

Current Liabilities - Additional Information (Detail) - USD ($) $ in Millions	Oct. 03, 2020	Dec. 31, 2019
Liabilities Current [Abstract]
Book overdrafts	$ 115.2	$ 116.4
Dividends payable, current	123	122.9
Accrued vacation and holiday pay	$ 121.8	$ 106.2

Fair Value Measurements - Sched

Fair Value Measurements - Schedule of Financial Assets and Liabilities Measured at Fair Value (Detail) - USD ($) $ in Thousands	Oct. 03, 2020	Dec. 31, 2019
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Short-term investments	$ 412,401	$ 300,040
Total assets	19,519,277	18,344,666
Reported Value Measurement [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents	2,539,777	1,229,000
Short-term investments	412,401	300,040
Restricted cash and cash equivalents	131,623
Total assets	3,083,801	1,529,040
Derivative contracts	(6,577)	(19,599)
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	2,539,777	1,229,000
Short-term investments	412,401	300,040
Restricted cash and cash equivalents	131,623
Total assets	3,083,801	1,529,040
Significant Other Observable Inputs (Level 2) [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative contracts	$ (6,577)	$ (19,599)

Fair Value Measurements - Addit

Fair Value Measurements - Additional Information (Detail) - USD ($) $ in Millions	Oct. 03, 2020	Dec. 31, 2019
Fair Value Disclosures [Abstract]
Fair value of short-term and long-term debt, including current maturities	$ 6,280	$ 4,810

Contingencies - Additional Info

Contingencies - Additional Information (Detail) - USD ($) $ in Millions	Oct. 03, 2020	Dec. 31, 2019
Commitments And Contingencies Disclosure [Abstract]
Accrual for environmental loss contingencies, gross	$ 16.6	$ 16.4
Accrued environmental loss contingencies, current	6.3	4.1
Accrued environmental loss contingencies, noncurrent	$ 10.3	$ 12.3

Stock-Based Compensation - Addi

Stock-Based Compensation - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Oct. 03, 2020	Sep. 28, 2019	Oct. 03, 2020	Sep. 28, 2019	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%
Compensation expenses for stock options	$ 0.3	$ 0.3	$ 2.4	$ 4.4
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	2.8		$ 2.8
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	64.2		$ 64.2
Weighted-average recognition period for unrecognized compensation expense related to stock (years)			1 year 6 months
Compensation expense	$ 11.1	11	$ 47.9	59.1
Omnibus Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock based compensation, common stock available for grant	7,800,000		7,800,000
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	1,000,000		1,000,000
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 Awards and Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense related to stock	$ 1.6		$ 1.6
Weighted-average recognition period for unrecognized compensation expense related to stock (years)			1 year 7 months 6 days
Compensation expense	$ 3.3	$ 1.8	$ 5.8	$ 10.9

Stock-Based Compensation - Sche

Stock-Based Compensation - Schedule of Stock Option Plans Activity (Detail) $ / shares in Units, shares in Thousands, $ in Thousands	9 Months Ended
	Oct. 03, 2020USD ($)$ / sharesshares
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Outstanding at beginning of year, Shares | shares	3,892
Granted, Shares | shares	529
Canceled, Shares | shares	(239)
Outstanding at end of year, Shares | shares	4,182
Options exercisable at end of year, Shares | shares	3,435
Outstanding at beginning of year, Weighted - Average Exercise Price | $ / shares	$ 50.78
Granted, Weighted - Average Exercise Price | $ / shares	42.46
Canceled, Weighted - Average Exercise Price | $ / shares	51.58
Outstanding at end of period, Weighted - Average Exercise Price | $ / shares	49.68
Options exercisable at end of year, Weighted - Average Exercise Price | $ / shares	$ 50.36
Outstanding, Weighted - Average Remaining Contractual Life	6 years
Stock options exercisable, Weighted - Average Remaining Contractual Life	5 years 3 months 18 days
Outstanding at end of year, Aggregate Intrinsic Value | $	$ 3,846
Stock options exercisable, Aggregate Intrinsic Value | $	$ 2,189

Stock-Based Compensation - Summ

Stock-Based Compensation - Summary of Nucor's RSU Activity (Detail) - Restricted Stock Units [Member] shares in Thousands	9 Months Ended
	Oct. 03, 2020$ / sharesshares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested at beginning of year, Shares | shares	1,776
Granted, Shares | shares	1,246
Vested, Shares | shares	(1,140)
Canceled, Shares | shares	(22)
Unvested at end of year, Shares | shares	1,860
Unvested at beginning of year, Grant Date Fair Value | $ / shares	$ 52.60
Granted, Grant Date Fair Value | $ / shares	42.46
Vested, Grant Date Fair Value | $ / shares	50.14
Canceled, Grant Date Fair Value | $ / shares	50.17
Unvested at end of year, Grant Date Fair Value | $ / shares	$ 47.34

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	9 Months Ended
	Oct. 03, 2020$ / sharesshares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested at beginning of year, Shares | shares	147
Granted, Shares | shares	348
Vested, Shares | shares	(359)
Unvested at end of year, Shares | shares	136
Unvested at beginning of year, Grant Date Fair Value | $ / shares	$ 60.81
Granted, Grant Date Fair Value | $ / shares	36.15
Vested, Grant Date Fair Value | $ / shares	40.98
Unvested at end of year, Grant Date Fair Value | $ / shares	$ 49.98

Employee Benefit Plan - Additio

Employee Benefit Plan - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Oct. 03, 2020	Sep. 28, 2019	Oct. 03, 2020	Sep. 28, 2019
Employee Benefit Plan [Abstract]
Profit Sharing and Retirement Savings Plan, plan expense	$ 27.5	$ 40	$ 59.5	$ 163.7

Interest Expense (Income) - Sch

Interest Expense (Income) - Schedule of Components of Net Interest Expense (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 03, 2020	Sep. 28, 2019	Oct. 03, 2020	Sep. 28, 2019
Interest Revenue Or Expense Net [Abstract]
Interest expense	$ 42,281	$ 40,721	$ 128,726	$ 119,736
Interest income	(2,142)	(9,435)	(11,870)	(26,977)
Interest expense, net	$ 40,139	$ 31,286	$ 116,856	$ 92,759

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended
	Oct. 03, 2020	Sep. 28, 2019	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Effective income tax rate	23.30%	22.80%
Non-current deferred tax liabilities included in deferred credits and other liabilities	$ 575.2		$ 431

Stockholders' Equity - Addition

Stockholders' Equity - Additional Information (Detail) - USD ($)	3 Months Ended		9 Months Ended
	Oct. 03, 2020	Sep. 28, 2019	Oct. 03, 2020	Sep. 28, 2019	Sep. 06, 2018
Dividends declared per share	$ 0.4025	$ 0.40	$ 1.2075	$ 1.20
Common Stock [Member]
Share repurchase program, available repurchase amount	$ 1,160,000,000		$ 1,160,000,000
Common Stock [Member] | Maximum [Member]
Stock Repurchase Program, Authorized Amount					$ 2,000,000,000
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		9 Months Ended
	Oct. 03, 2020	Sep. 28, 2019	Oct. 03, 2020	Sep. 28, 2019
BALANCES, beginning of period	$ 10,623,485	$ 10,698,008	$ 10,791,176	$ 10,201,968
Net earnings	222,630	293,587	410,162	1,236,657
Other comprehensive income (loss)	25,367	(16,006)	(12,503)	(11,519)
Stock options exercised				5,892
Stock option expense	263	275	2,402	4,387
Issuance of stock under award plans, net of forfeitures	11,189	11,339	38,996	59,608
Amortization of unearned compensation	400	500	1,300	1,500
Treasury stock value acquired			(39,499)	(197,511)
Cash dividends declared	(123,039)	(122,809)	(368,774)	(368,707)
Distributions to noncontrolling interests	(43,228)	(3,861)	(106,193)	(71,241)
Other				(1)
BALANCES, end of period	10,717,067	10,861,033	10,717,067	10,861,033
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	$ 2,106,907	$ 2,098,809	$ 2,107,646	$ 2,073,715
Stock options exercised				808
Stock option expense	263	275	2,402	4,387
Issuance of stock under award plans, net of forfeitures	10,012	9,365	6,234	28,540
Amortization of unearned compensation	400	500	1,300	1,500
Other		(1)		(2)
BALANCES, end of period	2,117,582	2,108,948	2,117,582	2,108,948
Retained Earnings [Member]
BALANCES, beginning of period	10,998,533	10,977,950	11,115,056	10,337,445
Net earnings	193,415	275,031	322,627	1,163,320
Cash dividends declared	(123,039)	(122,809)	(368,774)	(368,707)
Other	(1)		(1)	(1,886)
BALANCES, end of period	11,068,908	11,130,172	11,068,908	11,130,172
Accumulated Other Comprehensive Income (Loss) [Member]
BALANCES, beginning of period	(340,836)	(297,760)	(302,966)	(304,133)
Other comprehensive income (loss)	25,367	(16,006)	(12,503)	(11,519)
Other				1,886
BALANCES, end of period	(315,469)	(313,766)	(315,469)	(313,766)
Treasury Stock (at cost) [Member]
BALANCES, beginning of period	$ (2,721,845)	$ (2,630,343)	$ (2,713,931)	$ (2,467,010)
BALANCES, shares at beginning of period	78,259	76,997	78,342	74,562
Stock options exercised				$ 5,084
Stock options exercised (in shares)				(153)
Issuance of stock under award plans, net of forfeitures	$ 1,177	$ 1,974	$ 32,762	$ 31,068
Issuance of stock under award plans, net of forfeitures, shares	(34)	(58)	(942)	(920)
Treasury stock value acquired			$ (39,499)	$ (197,511)
Treasury stock acquired (in shares)			825	3,450
Other		$ 1		$ 1
BALANCES, end of period	$ (2,720,668)	$ (2,628,368)	$ (2,720,668)	$ (2,628,368)
BALANCES, shares at end of period	78,225	76,939	78,225	76,939
Total Nucor Stockholders' Equity [Member]
BALANCES, beginning of period	$ 10,194,820	$ 10,300,717	$ 10,357,866	$ 9,792,078
Net earnings	193,415	275,031	322,627	1,163,320
Other comprehensive income (loss)	25,367	(16,006)	(12,503)	(11,519)
Stock options exercised				5,892
Stock option expense	263	275	2,402	4,387
Issuance of stock under award plans, net of forfeitures	11,189	11,339	38,996	59,608
Amortization of unearned compensation	400	500	1,300	1,500
Treasury stock value acquired			(39,499)	(197,511)
Cash dividends declared	(123,039)	(122,809)	(368,774)	(368,707)
Other	(1)		(1)	(1)
BALANCES, end of period	10,302,414	10,449,047	10,302,414	10,449,047
Noncontrolling Interests [Member]
BALANCES, beginning of period	428,665	397,291	433,310	409,890
Net earnings	29,215	18,556	87,535	73,337
Distributions to noncontrolling interests	(43,228)	(3,861)	(106,193)	(71,241)
Other	1		1
BALANCES, end of period	$ 414,653	$ 411,986	$ 414,653	$ 411,986

Accumulated Other Comprehensi_3

Accumulated Other Comprehensive Income (Loss) - Components of Accumulated Other Comprehensive Income (Loss) (Detail) - USD ($) $ in Thousands	3 Months Ended				9 Months Ended
	Oct. 03, 2020		Sep. 28, 2019		Oct. 03, 2020		Sep. 28, 2019
Accumulated Other Comprehensive Income Loss Net Of Tax [Abstract]
Beginning Balance, Gains and (Losses) on Hedging Derivatives	$ (10,900)		$ (11,100)		$ (14,000)		$ (6,500)
Other comprehensive income (loss) before reclassifications, Gains and (Losses) on Hedging Derivatives	6,387		(3,315)		4,888		(7,801)
Amounts reclassified from accumulated other comprehensive (loss) income into earnings, Gains and (Losses) on Hedging Derivatives	2,113	[1]	1,615	[2]	6,712	[1]	1,501	[2]
Net current-period other comprehensive income (loss), Gains and (Losses) on Hedging Derivatives	8,500		(1,700)		11,600		(6,300)
Ending Balance, Gains and (Losses) on Hedging Derivatives	(2,400)		(12,800)		(2,400)		(12,800)
Beginning Balance, Foreign Currency Gains (Loss)	(337,743)		(295,559)		(296,773)		(304,646)
Other comprehensive income (loss) before reclassifications, Foreign Currency Gains (Loss)	16,867		(14,306)		(24,103)		(5,219)
Net current-period other comprehensive income (loss), Foreign Currency Gains (Loss)	16,867		(14,306)		(24,103)		(5,219)
Ending Balance, Foreign Currency Gains (Loss)	(320,876)		(309,865)		(320,876)		(309,865)
Beginning Balance, Adjustment to Early Retiree Medical Plan	7,807		8,899		7,807		7,013
Accumulated other comprehensive income loss defined benefit pension and other postretirement plans other net of tax							1,886
Ending Balance, Adjustment to Early Retiree Medical Plan	7,807		8,899		7,807		8,899
Beginning Balance	(340,836)		(297,760)		(302,966)		(304,133)
Other comprehensive income (loss) before reclassifications	23,254		(17,621)		(19,215)		(13,020)
Amounts reclassified from accumulated other comprehensive income (loss) into earnings	2,113	[1]	1,615	[2]	6,712	[1]	1,501	[2]
Net current-period other comprehensive income (loss)	25,367		(16,006)		(12,503)		(11,519)
Accumulated other comprehensive income loss other net of tax							1,886
Ending Balance	$ (315,469)		$ (313,766)		$ (315,469)		$ (313,766)
[1]	Includes $2,113 and $6,712 of accumulated other comprehensive income (loss) reclassifications into cost of products sold for net losses on commodity contracts in the third quarter and first nine months of 2020, respectively. The tax impacts of those reclassifications were $700 and $2,300 in the third quarter and first nine months of 2020, respectively.
[2]	Includes $1,615 and $1,501 of accumulated other comprehensive income (loss) reclassifications into cost of products sold for net losses on commodity contracts in the third quarter and first nine months of 2019, respectively. The tax impacts of those reclassifications were $500 in both the third quarter and first nine months of 2019.

Accumulated Other Comprehensi_4

Accumulated Other Comprehensive Income (Loss) - Components of Accumulated Other Comprehensive Income (Loss) (Parenthetical) (Detail) - USD ($) $ in Thousands	3 Months Ended				9 Months Ended
	Oct. 03, 2020		Sep. 28, 2019		Oct. 03, 2020		Sep. 28, 2019
Accumulated Other Comprehensive Income (Loss) [Line Items]
Amounts reclassified from accumulated other comprehensive (loss) income into earnings, Gains and (Losses) on Hedging Derivatives	$ 2,113	[1]	$ 1,615	[2]	$ 6,712	[1]	$ 1,501	[2]
AOCI reclassification impact on tax	700		500		2,300		500
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	2,113		1,615		6,712		1,501
AOCI reclassification impact on tax	$ 700		$ 500		$ 2,300		$ 500
[1]	Includes $2,113 and $6,712 of accumulated other comprehensive income (loss) reclassifications into cost of products sold for net losses on commodity contracts in the third quarter and first nine months of 2020, respectively. The tax impacts of those reclassifications were $700 and $2,300 in the third quarter and first nine months of 2020, respectively.
[2]	Includes $1,615 and $1,501 of accumulated other comprehensive income (loss) reclassifications into cost of products sold for net losses on commodity contracts in the third quarter and first nine months of 2019, respectively. The tax impacts of those reclassifications were $500 in both the third quarter and first nine months of 2019.

Accumulated Other Comprehensi_5

Accumulated Other Comprehensive Income (Loss) - Additional Information (Detail) - USD ($) $ in Thousands	Oct. 03, 2020	Jul. 04, 2020	Dec. 31, 2019	Sep. 28, 2019	Jun. 29, 2019	Dec. 31, 2018
Accumulated Other Comprehensive Income (Loss) [Line Items]
Losses related to foreign currency/equity method investment/operations	$ (320,876)	$ (337,743)	$ (296,773)	$ (309,865)	$ (295,559)	$ (304,646)
Canadian Operations [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Losses related to foreign currency/equity method investment/operations	(129,400)
Duferdofin Nucor S.r.l. [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Losses related to foreign currency/equity method investment/operations	$ (191,500)

Segments - Segments (Detail)

Segments - Segments (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 03, 2020	Sep. 28, 2019	Oct. 03, 2020	Sep. 28, 2019	Dec. 31, 2019
Segment Reporting Information [Line Items]
Net sales	$ 4,927,960	$ 5,464,502	$ 14,879,603	$ 17,457,112
Earnings (loss) before income taxes and noncontrolling interests	290,418	380,339	617,772	1,604,577
Total assets	19,519,277		19,519,277		$ 18,344,666
Operating Segments [Member] | Steel Mills [Member]
Segment Reporting Information [Line Items]
Net sales	2,842,625	3,244,473	8,875,856	10,897,322
Earnings (loss) before income taxes and noncontrolling interests	205,152	309,939	512,082	1,578,257
Total assets	9,251,790		9,251,790		9,283,216
Operating Segments [Member] | Steel Products [Member]
Segment Reporting Information [Line Items]
Net sales	1,738,004	1,820,359	4,988,026	5,225,064
Earnings (loss) before income taxes and noncontrolling interests	186,976	170,214	502,409	363,731
Total assets	4,399,501		4,399,501		4,610,628
Operating Segments [Member] | Raw Materials [Member]
Segment Reporting Information [Line Items]
Net sales	347,331	399,670	1,015,721	1,334,726
Earnings (loss) before income taxes and noncontrolling interests	6,232	(10,599)	(3,068)	64,333
Total assets	3,172,464		3,172,464		3,316,479
Intercompany Eliminations [Member] | Steel Mills [Member]
Segment Reporting Information [Line Items]
Net sales	731,942	825,237	2,264,278	2,542,008
Intercompany Eliminations [Member] | Steel Products [Member]
Segment Reporting Information [Line Items]
Net sales	51,029	57,517	197,603	174,718
Intercompany Eliminations [Member] | Raw Materials [Member]
Segment Reporting Information [Line Items]
Net sales	1,863,796	2,063,167	5,772,583	6,917,523
Corporate and Eliminations Items [Member]
Segment Reporting Information [Line Items]
Net sales	(2,646,767)	(2,945,921)	(8,234,464)	(9,634,249)
Earnings (loss) before income taxes and noncontrolling interests	(107,942)	$ (89,215)	(393,651)	$ (401,744)
Total assets	$ 2,695,522		$ 2,695,522		$ 1,134,343

Revenue - Schedule of Net Sales

Revenue - Schedule of Net Sales Disaggregates by Major Source (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 03, 2020	Sep. 28, 2019	Oct. 03, 2020	Sep. 28, 2019
Revenue from Contract with Customers [Line Items]
Revenues	$ 4,927,960	$ 5,464,502	$ 14,879,603	$ 17,457,112
Sheet [Member]
Revenue from Contract with Customers [Line Items]
Revenues	1,256,537	1,513,884	3,899,970	5,071,027
Bar [Member]
Revenue from Contract with Customers [Line Items]
Revenues	957,216	979,082	2,830,936	3,173,289
Structural [Member]
Revenue from Contract with Customers [Line Items]
Revenues	362,192	378,670	1,159,949	1,214,355
Plate [Member]
Revenue from Contract with Customers [Line Items]
Revenues	266,680	372,837	985,001	1,438,651
Tubular Products [Member]
Revenue from Contract with Customers [Line Items]
Revenues	274,915	296,519	830,283	919,711
Rebar Fabrication [Member]
Revenue from Contract with Customers [Line Items]
Revenues	463,286	469,180	1,300,518	1,249,912
Other Steel Products [Member]
Revenue from Contract with Customers [Line Items]
Revenues	999,803	1,054,660	2,857,225	3,055,441
Raw Materials [Member]
Revenue from Contract with Customers [Line Items]
Revenues	347,331	399,670	1,015,721	1,334,726
Steel Mills [Member]
Revenue from Contract with Customers [Line Items]
Revenues	2,842,625	3,244,473	8,875,856	10,897,322
Steel Mills [Member] | Sheet [Member]
Revenue from Contract with Customers [Line Items]
Revenues	1,256,537	1,513,884	3,899,970	5,071,027
Steel Mills [Member] | Bar [Member]
Revenue from Contract with Customers [Line Items]
Revenues	957,216	979,082	2,830,936	3,173,289
Steel Mills [Member] | Structural [Member]
Revenue from Contract with Customers [Line Items]
Revenues	362,192	378,670	1,159,949	1,214,355
Steel Mills [Member] | Plate [Member]
Revenue from Contract with Customers [Line Items]
Revenues	266,680	372,837	985,001	1,438,651
Steel Products [Member]
Revenue from Contract with Customers [Line Items]
Revenues	1,738,004	1,820,359	4,988,026	5,225,064
Steel Products [Member] | Tubular Products [Member]
Revenue from Contract with Customers [Line Items]
Revenues	274,915	296,519	830,283	919,711
Steel Products [Member] | Rebar Fabrication [Member]
Revenue from Contract with Customers [Line Items]
Revenues	463,286	469,180	1,300,518	1,249,912
Steel Products [Member] | Other Steel Products [Member]
Revenue from Contract with Customers [Line Items]
Revenues	999,803	1,054,660	2,857,225	3,055,441
Raw Materials [Member]
Revenue from Contract with Customers [Line Items]
Revenues	347,331	399,670	1,015,721	1,334,726
Raw Materials [Member] | Raw Materials [Member]
Revenue from Contract with Customers [Line Items]
Revenues	$ 347,331	$ 399,670	$ 1,015,721	$ 1,334,726

Revenue - Additional Informatio

Revenue - Additional Information (Detail) - USD ($) $ in Millions	Oct. 03, 2020	Dec. 31, 2019
Revenue From Contract With Customer [Abstract]
Contract liabilities	$ 114.3	$ 108.6

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		9 Months Ended
	Oct. 03, 2020	Sep. 28, 2019	Oct. 03, 2020	Sep. 28, 2019
Earnings Per Share [Abstract]
Basic net earnings	$ 193,415	$ 275,031	$ 322,627	$ 1,163,320
Earnings allocated to participating securities, Basic	(1,201)	(1,655)	(2,182)	(6,295)
Net earnings available to common stockholders, Basic	$ 192,214	$ 273,376	$ 320,445	$ 1,157,025
Basic average shares outstanding	303,394	304,637	303,072	305,553
Basic net earnings per share	$ 0.63	$ 0.90	$ 1.06	$ 3.79
Diluted net earnings	$ 193,415	$ 275,031	$ 322,627	$ 1,163,320
Earnings allocated to participating securities, Diluted	(1,202)	(1,656)	(2,182)	(6,295)
Net earnings available to common stockholders, Diluted	$ 192,213	$ 273,375	$ 320,445	$ 1,157,025
Dilutive effect of stock options and other	47	343	27	476
Diluted average shares outstanding	303,441	304,980	303,099	306,029
Diluted net earnings per share	$ 0.63	$ 0.90	$ 1.06	$ 3.78

Earnings Per Share - Anti-dilut

Earnings Per Share - Anti-dilutive Stock Options (Detail) - $ / shares shares in Thousands	3 Months Ended		9 Months Ended
	Oct. 03, 2020	Sep. 28, 2019	Oct. 03, 2020	Sep. 28, 2019
Earnings Per Share [Abstract]
Weighted-average shares	3,463	963	3,638	963
Weighted-average exercise price	$ 51.38	$ 60.92	$ 51.15	$ 60.92

Restricted Cash and Cash Equi_2

Restricted Cash and Cash Equivalents - Additional Information (Details) - USD ($) $ in Thousands	Oct. 03, 2020	Jul. 31, 2020
Restricted Cash And Cash Equivalents Items [Line Items]
Qualified expenditures for construction of facility	$ 31,000
Restricted cash and cash equivalents	$ 131,623
Variable Rate Green Bonds [Member]
Restricted Cash And Cash Equivalents Items [Line Items]
Debt instrument, issuance date	Jul. 27, 2020
Issuance of bonds	$ 162,600	$ 162,600
Debt instrument, term	40 years	40 years

Debt - Additional Information (

Debt - Additional Information (Details) - USD ($) $ in Millions	Oct. 03, 2020	Jul. 31, 2020	May 31, 2020
Debt Instrument [Line Items]
Net proceeds of debt issuances			$ 989.4
Debt issuance costs			8.4
Variable Rate Green Bonds [Member]
Debt Instrument [Line Items]
Issuance of bonds	$ 162.6	$ 162.6
Debt instrument, term	40 years	40 years
Notes, 2.000%, due 2025 [Member]
Debt Instrument [Line Items]
Debt instrument face amount			$ 500
Debt instrument interest rate			2.00%
Debt instrument - maturity year			2025
Notes, 2.700%, due 2030 [Member]
Debt Instrument [Line Items]
Debt instrument face amount			$ 500
Debt instrument interest rate			2.70%
Debt instrument - maturity year			2030

Subsequent Event - Additional I

Subsequent Event - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended			9 Months Ended
	Dec. 31, 2020	Oct. 03, 2020	Sep. 28, 2019	Oct. 03, 2020	Sep. 28, 2019
Subsequent Event [Line Items]
Provision for income taxes, approximate net benefit		$ (67,788)	$ (86,752)	$ (207,610)	$ (367,920)
Scenario Forecast [Member]
Subsequent Event [Line Items]
Provision for income taxes, approximate net benefit	$ 40,000