Income Taxes - Gross Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Reconciliation Of Unrecognized Tax Benefits Excluding Amounts Pertaining To Examined Tax Returns Roll Forward
Gross unrecognized tax benefits - beginning of year	$ 96,166	$ 109,462	$ 94,219
Increases in tax positions for prior years	19,679	2,169	20,931
Decreases in tax positions for prior years		(11,254)	(6,020)
Increases in tax positions for current year	17,712	15,149	13,709
Settlements with taxing authorities	495
Lapse in statute of limitations	(24,359)	(19,360)	(13,377)
Gross unrecognized tax benefits - end of year	$ 109,693	$ 96,166	$ 109,462

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 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 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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