Income Taxes - Reconciliation of the Beginning and Ending Uncertain Tax Positions (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Gross unrecognized tax benefits
Gross unrecognized tax benefits, Beginning balance	$ 167	$ 2,763	$ 2,678
Increases in tax positions for prior years	1	43	0
Decreases in tax positions for prior years	0	0	0
Decreases in tax positions for current year		210
Increases in tax positions for current year	44		132
Settlements	0	0	0
Lapse in statute of limitations	(39)	(2,429)	(47)
Gross unrecognized tax benefits, Ending balance	$ 173	$ 167	$ 2,763

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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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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Amount of decrease 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 settlements with taxing authorities.

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

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