Changes in Liability for Unrecognized Gross Tax Benefits (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Tax Contingency [Line Items]
Uncertain tax positions at beginning of year	$ 24,779	$ 20,250	$ 24,220
Additions for tax positions relating to current-year operations	3,827	3,515	2,436
Additions for tax positions relating to prior tax years	2,935	1,819	6,218
Subtractions for tax positions relating to prior tax years	(963)	(929)	(3,641)
Reductions in balance due to settlements	(122)	124	(8,983)
Uncertain tax positions at end of year	$ 30,456	$ 24,779	$ 20,250

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

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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 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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