Fair Value Measurements (Tables)

6 Months Ended

Jun. 30, 2018

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 are measured at fair value as of June 30, 2018 and December 31, 2017 (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 June 30, 2018
Assets:
Cash equivalents	$	1,178,986		$	1,178,986	$	—		$	—
Derivative contracts		6,455			—		6,455			—
Total assets	$	1,185,441		$	1,178,986	$	6,455		$	—
Liabilities:
Derivative contracts	$	(9,000	)	$	—	$	(9,000	)	$	—
As of December 31, 2017
Assets:
Cash equivalents	$	594,946		$	594,946	$	—		$	—
Short-term investments		50,000			50,000		—			—
Derivative contracts		479			—		479			—
Total assets	$	645,425		$	644,946	$	479		$	—
Liabilities:
Derivative contracts	$	(8,531	)	$	—	$	(8,531	)	$	—