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Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Line Items]
Unrecognized tax benefits	$ 23,559	$ 26,357
Unrecognized tax benefits that would impact effective tax rate	22,136	24,935
Unrecognized tax benefits, interest on income taxes accrued	3,682	4,223
Unrecognized tax benefits, excluding exchange rate differences in interest expense recognized	(533)	1,152
Accrued penalties	$ 958	$ 958

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Income Tax Disclosure [Line Items]

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Unrecognized Tax Benefits Interest on Income Taxes Expense Benefit

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Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15A
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6907707&loc=SL6600010-109319

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Unrecognized Tax Benefit
-URI http://asc.fasb.org/extlink&oid=6527854

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Amount of statutory penalties accrued for a tax position claimed or expected to be claimed by the entity, in its tax return.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32718-109319

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Amount of interest expense accrued for an underpayment of income taxes.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32718-109319

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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6907707&loc=SL6600010-109319

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