Accumulated Other Comprehensive Loss - Amounts Included in Accumulated Other Comprehensive Loss (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Accumulated Other Comprehensive Income (Loss)
Beginning Balance	$ (268,808)	$ (188,973)	$ (223,856)
Other comprehensive income (loss) before reclassifications	(1,952)	(88,242)	54,861
Amounts reclassified from accumulated other comprehensive loss	11,018	8,407	2,107
Other comprehensive income (loss)	9,066	(79,835)	56,968
Adoption of accounting standards update related to reclassification of certain tax effects			(22,085)
Ending Balance	(259,742)	(268,808)	(188,973)
Unrecognized Net Defined Benefit Plan Costs [Member]
Accumulated Other Comprehensive Income (Loss)
Beginning Balance	(154,466)	(104,822)	(83,105)
Other comprehensive income (loss) before reclassifications	4,895	(53,797)	(8,486)
Amounts reclassified from accumulated other comprehensive loss	10,469	4,153	2,193
Other comprehensive income (loss)	15,364	(49,644)	(6,293)
Adoption of accounting standards update related to reclassification of certain tax effects			(15,424)
Ending Balance	(139,102)	(154,466)	(104,822)
Change in Fair Value of Derivatives [Member]
Accumulated Other Comprehensive Income (Loss)
Beginning Balance	(1,008)	(89)	540
Other comprehensive income (loss) before reclassifications	(2,723)	(766)	(527)
Amounts reclassified from accumulated other comprehensive loss	549	(153)	(86)
Other comprehensive income (loss)	(2,174)	(919)	(613)
Adoption of accounting standards update related to reclassification of certain tax effects			(16)
Ending Balance	(3,182)	(1,008)	(89)
Foreign Currency Translation [Member]
Accumulated Other Comprehensive Income (Loss)
Beginning Balance	(113,334)	(84,062)	(141,291)
Other comprehensive income (loss) before reclassifications	(4,124)	(33,679)	63,874
Amounts reclassified from accumulated other comprehensive loss	0	4,407	0
Other comprehensive income (loss)	(4,124)	(29,272)	63,874
Adoption of accounting standards update related to reclassification of certain tax effects			(6,645)
Ending Balance	(117,458)	(113,334)	(84,062)
AOCI Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss)
Adoption of accounting standards update related to reclassification of certain tax effects	$ (593)	$ 9,061	$ 22,085

Adjustments to Equity, Reclassification of Taxes, Effects of New Accounting Standards Update, Retained Earnings

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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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Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

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

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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

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