Income Taxes - Summary of Changes in Liability Related to Unrecognized Tax Benefits (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Abstract]
Unrecognized tax benefit liability, Beginning Balance	$ 5,740	$ 6,693	$ 9,097
Prior period positions:
Increases	175	181	409
Decreases		(66)	(233)
Increases from current period positions	184	195	799
Settlements		(897)	(1,721)
Lapse of statute of limitations	(1,114)	(170)	(1,164)
Other	(230)	(196)	(494)
Unrecognized tax benefit liability, Ending Balance	$ 4,755	$ 5,740	$ 6,693

Unrecognized tax benefits increase decrease resulting from other adjustments.

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

+ References

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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 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 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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