Accumulated Other Comprehensive Income (Loss) - Schedule of Changes in Accumulated Other Comprehensive Income (Loss) (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Accumulated other comprehensive loss, net of tax	$ 6,217,304
Accumulated other comprehensive loss, net of tax	6,311,153	$ 6,217,304
Foreign Currency Translation Adjustments
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Accumulated other comprehensive loss, net of tax	(373,043)	(396,996)	$ (297,416)
OCI before reclassifications	88,132	23,953	(99,580)
Amounts reclassified from AOCI	0	0	0
Net current period other comprehensive income (loss)	88,132	23,953	(99,580)
Accumulated other comprehensive loss, net of tax	(284,911)	(373,043)	(396,996)
(Losses) Gains on Derivatives Qualifying as Hedges
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Accumulated other comprehensive loss, net of tax	2,068	4,746	(10,332)
OCI before reclassifications	(5,076)	4,969	8,011
Amounts reclassified from AOCI	(3,862)	(7,647)	7,067
Net current period other comprehensive income (loss)	(8,938)	(2,678)	15,078
Accumulated other comprehensive loss, net of tax	(6,870)	2,068	4,746
Pension and Postretirement Liability Adjustment
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Accumulated other comprehensive loss, net of tax	(345,919)	(309,977)	(329,734)
OCI before reclassifications	(73,735)	(45,599)	9,717
Amounts reclassified from AOCI	13,894	9,657	10,040
Net current period other comprehensive income (loss)	(59,841)	(35,942)	19,757
Accumulated other comprehensive loss, net of tax	(405,760)	(345,919)	(309,977)
Total
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Accumulated other comprehensive loss, net of tax	(716,894)	(702,227)	(637,482)
OCI before reclassifications	9,321	(16,677)	(81,852)
Amounts reclassified from AOCI	10,032	2,010	17,107
Net current period other comprehensive income (loss)	19,353	(14,667)	(64,745)
Accumulated other comprehensive loss, net of tax	$ (697,541)	$ (716,894)	$ (702,227)

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount after tax, before reclassification adjustments, of other comprehensive income (loss), attributable to parent.

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Amount after tax of other comprehensive income (loss) attributable to parent entity.

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Amount after tax of reclassification adjustments of other comprehensive income (loss) attributable to parent.

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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