Income Taxes - Changes in Valuation Allowance for Deferred Tax Assets (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Beginning balance	$ 281,473	$ 279,867	$ 194,739
Charged to expense	(54,816)	10,095	95,757
NOL/tax credit claimed/expired	(1,928)	(872)	(1,197)
Translation adjustments	26,403	(7,617)	(9,432)
Ending balance	$ 251,132	$ 281,473	$ 279,867

Deferred tax assets valuation allowance charged to expense income.

No definition available.

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- Definition

Deferred tax assets valuation allowance foreign currency translation adjustment.

+ References

No definition available.

+ Details

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- Definition

Deferred Tax Assets Valuation Allowances On Net Operating Loss and Tax Credit Expiration

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No definition available.

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- Definition

Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32537-109319

+ Details

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- References

No definition available.

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