Amounts Included in Accumulated Other Comprehensive Loss (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Accumulated Other Comprehensive Income (Loss)
Beginning Balance	$ (223,856)	$ (208,806)	$ (165,624)
Other comprehensive income (loss) before reclassifications	54,861	(19,303)	(46,923)
Amounts reclassified from accumulated other comprehensive loss	2,107	4,253	3,741
Other comprehensive income (loss)	56,968	(15,050)	(43,182)
Ending Balance	(188,973)	(223,856)	(208,806)
Unrecognized Net Defined Benefit Plan Costs [Member]
Accumulated Other Comprehensive Income (Loss)
Beginning Balance	(83,105)	(84,280)	(89,252)
Other comprehensive income (loss) before reclassifications	(8,486)	(1,991)	2,851
Amounts reclassified from accumulated other comprehensive loss	2,193	3,166	2,121
Other comprehensive income (loss)	(6,293)	1,175	4,972
Adoption of accounting standards update related to reclassification of certain tax effects	(15,424)
Ending Balance	(104,822)	(83,105)	(84,280)
Change in Fair Value of Derivatives [Member]
Accumulated Other Comprehensive Income (Loss)
Beginning Balance	540	(988)	(1,198)
Other comprehensive income (loss) before reclassifications	(527)	441	(1,410)
Amounts reclassified from accumulated other comprehensive loss	(86)	1,087	1,620
Other comprehensive income (loss)	(613)	1,528	210
Adoption of accounting standards update related to reclassification of certain tax effects	(16)
Ending Balance	(89)	540	(988)
Foreign Currency Translation [Member]
Accumulated Other Comprehensive Income (Loss)
Beginning Balance	(141,291)	(123,538)	(75,174)
Other comprehensive income (loss) before reclassifications	63,874	(17,753)	(48,364)
Amounts reclassified from accumulated other comprehensive loss	0	0	0
Other comprehensive income (loss)	63,874	(17,753)	(48,364)
Adoption of accounting standards update related to reclassification of certain tax effects	(6,645)
Ending Balance	(84,062)	(141,291)	(123,538)
AOCI Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss)
Other comprehensive income (loss)	56,968	$ (15,050)	$ (43,182)
Adoption of accounting standards update related to reclassification of certain tax effects	$ (22,085)

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

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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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No definition available.

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- Definition

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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