Debt instrument maturity year.

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- Definition

Issuance of bonds.

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No definition available.

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Line of credit facility expiration month and year.

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- Definition

Cash outflow related to payment of premium related to debt exchange.

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No definition available.

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- Definition

Ratio Of Funded Debt To Total Capital

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No definition available.

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- Definition

Ratio On The Limit Of Funded Debt To Capital On Credit Facility

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No definition available.

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- Definition

Face (par) amount of debt instrument at time of issuance.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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- Definition

The maximum amount of borrowing capacity under a line of credit that is available as of the balance sheet date for a specific purpose other than for financing goods acquired for inventory or imminent delivery to a customer.

+ References

No definition available.

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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- Definition

The cash inflow from additional borrowings, net of cash paid to third parties in connection with debt origination.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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Debt and Other Financing Arrangements - Additional Information (Detail) - USD ($)		1 Months Ended				3 Months Ended	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2020	Jul. 31, 2020	May 31, 2020	Apr. 30, 2018	Jun. 30, 2018	Dec. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Annual aggregate long-term debt maturities - 2021	$ 0	$ 0					$ 0
Annual aggregate long-term debt maturities - 2022	601,000,000.0	601,000,000.0					601,000,000.0
Annual aggregate long-term debt maturities - 2023	500,000,000.0	500,000,000.0					500,000,000.0
Annual aggregate long-term debt maturities - 2024	0	0					0
Annual aggregate long-term debt maturities - 2025	500,000,000.0	500,000,000.0					500,000,000.0
Annual aggregate long-term debt maturities - thereafter	3,800,000,000	3,800,000,000					3,800,000,000
Net proceeds of debt issuances				$ 989,400,000	$ 986,100,000
Debt issuance costs	30,859,000	30,859,000		8,400,000	11,900,000		$ 30,859,000	$ 25,259,000
Ratio funded debt to total capital							32.00%
Payment of premium component of debt exchange		180,300,000					$ 180,383,000
Credit facilities, amount outstanding	57,906,000	57,906,000					57,906,000	62,444,000
Variable Rate Green Bonds [Member]
Debt Instrument [Line Items]
Issuance of bonds	$ 162,600,000		$ 162,600,000
Debt instrument, term	40 years		40 years
Notes, 3.950%, due 2028 [Member]
Debt Instrument [Line Items]
Debt instrument face amount	$ 500,000,000	$ 500,000,000			$ 500,000,000.0		$ 500,000,000	500,000,000
Debt instrument interest rate	3.95%	3.95%			3.95%		3.95%
Debt instrument - maturity year					2028		2028
Notes, 4.400%, due 2048 [Member]
Debt Instrument [Line Items]
Debt instrument face amount	$ 329,219,000	$ 329,219,000			$ 500,000,000.0		$ 329,219,000	500,000,000
Debt instrument interest rate	4.40%	4.40%			4.40%		4.40%
Debt instrument - maturity year					2048		2048
Notes, 5.85%, due June 1st, 2018 [Member]
Debt Instrument [Line Items]
Debt instrument face amount					$ 500,000,000.0
Debt instrument interest rate					5.85%
Debt instrument - maturity year					2018
Repayments of debt					$ 500,000,000.0
Debt instrument - maturity date					Jun. 01, 2018
Notes, 2.000%, due 2025 [Member]
Debt Instrument [Line Items]
Debt instrument face amount				$ 500,000,000.0
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				$ 500,000,000.0
Debt instrument interest rate				2.70%
Debt instrument - maturity year				2030
Notes, 6.400%, due 2037 [Member]
Debt Instrument [Line Items]
Debt instrument face amount	$ 543,331,000	$ 543,331,000					$ 543,331,000	650,000,000
Debt instrument interest rate	6.40%	6.40%					6.40%
Debt instrument - maturity year							2037
Notes, 5.200%, due 2043 [Member]
Debt Instrument [Line Items]
Debt instrument face amount	$ 338,133,000	$ 338,133,000					$ 338,133,000	500,000,000
Debt instrument interest rate	5.20%	5.20%					5.20%
Debt instrument - maturity year							2043
Notes, 2.979%, due 2055 [Member]
Debt Instrument [Line Items]
Debt instrument face amount	$ 439,317,000	$ 439,317,000					$ 439,317,000
Debt instrument interest rate	2.979%	2.979%					2.979%
Debt instrument - maturity year		2055					2055
Harris Steel [Member]
Debt Instrument [Line Items]
Credit facility availability	$ 19,600,000	$ 19,600,000					$ 19,600,000	19,600,000
Credit facilities, amount outstanding	0	0					0	0
Amended and Restated Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Credit facility availability						$ 1,500,000,000
Line of revolving credit facility expiration date						2023-04
Ratio on the limit of funded debt to capital on credit facility						60.00%
Credit facilities, amount outstanding								0
Letter of Credit [Member]
Debt Instrument [Line Items]
Credit facility availability						$ 100,000,000.0
Credit facilities, amount outstanding	63,300,000	63,300,000					63,300,000	28,000,000.0
Letter of Credit [Member] \| Nucor Trading S.A. [Member]
Debt Instrument [Line Items]
Credit facilities, amount outstanding	57,900,000	57,900,000					57,900,000	$ 62,400,000
Foreign Currency Loans [Member] \| Amended and Restated Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Credit facility availability						850,000,000.0
Revolving Loans For Nucor Subsidiaries [Member] \| Amended and Restated Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Credit facility availability						500,000,000.0
Additional Commitments at Nucor's Election in Accordance with Terms of Credit Agreement [Member] \| Amended and Restated Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Credit facility availability						$ 500,000,000.0
Exchanged Debt [Member] \| Notes, 4.400%, due 2048 [Member]
Debt Instrument [Line Items]
Debt instrument face amount	$ 170,800,000	$ 170,800,000					$ 170,800,000
Debt instrument interest rate	4.40%	4.40%					4.40%
Debt instrument - maturity year		2048
Exchanged Debt [Member] \| Notes, 6.400%, due 2037 [Member]
Debt Instrument [Line Items]
Debt instrument face amount	$ 106,700,000	$ 106,700,000					$ 106,700,000
Debt instrument interest rate	6.40%	6.40%					6.40%
Debt instrument - maturity year		2037
Exchanged Debt [Member] \| Notes, 5.200%, due 2043 [Member]
Debt Instrument [Line Items]
Debt instrument face amount	$ 161,900,000	$ 161,900,000					$ 161,900,000
Debt instrument interest rate	5.20%	5.20%					5.20%
Debt instrument - maturity year		2043