Change in the Amount of Unrecognized Tax Benefits (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Sep. 30, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Unrecognized tax benefit, beginning balance		$ 11,777	$ 15,314	$ 18,283
Increases for tax positions related to the current year		733	600	627
Decreases for tax positions related to prior years	$ (4,000)	(16)	0	(3,239)
Increases for tax positions related to prior years		104	50	173
Decreases relating to settlements with taxing authorities		0	(3,805)	(384)
Increases acquired in business acquisitions		617	0	0
Foreign currency translation		(1)	(24)	(26)
Reductions due to lapsed statute of limitations		(1,834)	(358)	(120)
Unrecognized tax benefit, ending balance		$ 11,380	$ 11,777	$ 15,314

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Amount of unrecognized tax benefits.

+ 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=65882285&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 decrease in unrecognized tax benefits resulting from foreign currency translation.

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Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities.

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Amount of increase in unrecognized tax benefits resulting from acquisitions.

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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

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Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

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