Income Taxes - Reconciliation of Gross Unrecognized Tax Benefits (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance at beginning of year	$ 40,478us-gaap_UnrecognizedTaxBenefits	$ 27,734us-gaap_UnrecognizedTaxBenefits	$ 29,128us-gaap_UnrecognizedTaxBenefits
Increases in tax positions for current year	0	18,230	230
Increases in tax positions for prior years	11,432	2,315	5,075
Decreases in tax positions for prior years	(21,194)	(6,192)	(3,697)
Settlement of tax matters	(4,203)	(1,232)	(2,127)
Lapse of applicable statutes of limitations	(50)	(377)	(875)
Balance at end of year	$ 26,463us-gaap_UnrecognizedTaxBenefits	$ 40,478us-gaap_UnrecognizedTaxBenefits	$ 27,734us-gaap_UnrecognizedTaxBenefits

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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

-Glossary Unrecognized Tax Benefit

-URI http://asc.fasb.org/extlink&oid=6527854

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-Publisher FASB

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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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-Publisher FASB

-Name Accounting Standards Codification

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

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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.

+ References

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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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