Taxes on Income - Roll-Forward of Total Amounts of Company's Unrecognized Tax Benefits (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Abstract]
Balance at beginning of year	$ 18,687	$ 19,633	$ 19,016
Increase in unrecognized tax benefits as a result of tax positions taken during the year	1,478	1,412	2,376
Increase (decrease) in unrecognized tax benefits as a result of tax positions taken during a prior year	974		(869)
Decrease in unrecognized tax benefits as a result of statue of limitation expirations and tax audits	(6,735)	(2,358)	(890)
Balance at end of year	$ 14,404	$ 18,687	$ 19,633

Unrecognized Tax Benefits Increase Decrease Resulting From Prior Period Tax Positions

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- References

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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 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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- Definition

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

+ References

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