Reconciliation of Total Amounts of Unrecognized Tax Benefits (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Taxes [Line Items]
Beginning uncertain tax benefits	$ 2,487	$ 1,674	$ 1,243
Prior year-increases	120
Prior year-decreases	(762)
Current year-increases	144	1,067	687
Current year-decreases for lapses in statutes of limitations	(439)	(254)	(256)
Ending uncertain tax benefits	$ 1,550	$ 2,487	$ 1,674

Income Taxes [Line Items]

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- Definition

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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- Definition

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

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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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