Employee Benefit Plans - Amounts Recognized in Consolidated Balance Sheets (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Retirement Benefits [Abstract]
Other long-term asset	$ 149,182	$ 73,520
Other current liability	(17,572)	(11,692)
Pension and other post-retirement liabilities	(265,216)	(247,201)
Amounts recognized in consolidated balance sheets	$ (133,606)	$ (185,373)

Amount of asset, recognized in statement of financial position, for overfunded defined benefit pension and other postretirement plans.

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Name:	us-gaap_DefinedBenefitPlanAssetsForPlanBenefitsNoncurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant