Income Taxes - Reconciliation of Reserve for Uncertain Tax Positions, Excluding Interest and Penalties (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Tax Disclosure [Abstract]
Gross balance at January 1	$ 115,969us-gaap_UnrecognizedTaxBenefits	$ 115,009us-gaap_UnrecognizedTaxBenefits	$ 108,036us-gaap_UnrecognizedTaxBenefits
Additions based on tax positions related to current year	16,880	2,318	3,704
Additions for tax positions of prior years	12,928	18,906	16,432
Reductions for tax positions of prior years	(8)	(7,910)	(7,917)
Expiration of statutes	(2,852)	(2,633)	(1,903)
Reduction due to Spin-off	(26,870)
Tax settlements	(7,235)	(9,721)	(3,343)
Gross balance at December 31	108,812us-gaap_UnrecognizedTaxBenefits	115,969us-gaap_UnrecognizedTaxBenefits	115,009us-gaap_UnrecognizedTaxBenefits
Related tax benefits	(1,064)	(2,038)	(9,981)
Net reserve at December 31	$ 107,748	$ 113,931	$ 105,028

Liabilities for uncertain tax positions excluding interests and penalties.

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Unrecognized tax benefit related tax benefit.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to the disposition of a business not qualifying as a discontinued operation.

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Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

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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 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.

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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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