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A brief description of status of the tax examination, significant findings to date, and the entity's position with respect to the findings.

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

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Income Taxes - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Income Taxes [Line Items]
Effective tax rate	28.90%	17.80%
Gross unrecognized tax benefits excluding interest and penalties	$ 19,508us-gaap_UnrecognizedTaxBenefits		$ 19,610us-gaap_UnrecognizedTaxBenefits
Net unrecognized tax benefit excluding interest and penalties that would impact effective tax rate	11,524
Accrued interest on unrecognized tax benefits	$ 638		$ 578
Income tax examination, description	The Company and its subsidiaries are subject to examination by federal, state and foreign tax authorities. The Internal Revenue Service commenced an examination of the Company's U.S. federal tax filings for tax years 2011 through 2013 during the quarter ended March 31, 2015.
Earliest Tax Year [Member]
Income Taxes [Line Items]
Income tax examination period	2011
Earliest Tax Year [Member] \| Internal Revenue Service (IRS) [Member]
Income Taxes [Line Items]
Open tax year	2011
Latest Tax Year [Member]
Income Taxes [Line Items]
Income tax examination period	2013