Income Taxes - Unrecognized Tax Benefits (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Tax Contingency [Line Items]
Beginning balance	$ 16,363us-gaap_UnrecognizedTaxBenefits	$ 14,067us-gaap_UnrecognizedTaxBenefits	$ 13,576us-gaap_UnrecognizedTaxBenefits
Reductions	0	0	0
Settlements	0	0	0
Lapses in statute of limitations			(137)
Ending balance	27,522us-gaap_UnrecognizedTaxBenefits	16,363us-gaap_UnrecognizedTaxBenefits	14,067us-gaap_UnrecognizedTaxBenefits
Federal [Member]
Income Tax Contingency [Line Items]
Tax positions related to current year, Additions	502	477	289
Tax positions related to prior year, Additions		636	37
State [Member]
Income Tax Contingency [Line Items]
Tax positions related to current year, Additions	6,141	381	302
Tax positions related to prior year, Additions	5,258
Foreign [Member]
Income Tax Contingency [Line Items]
Tax positions related to prior year, Additions		802
Reductions	$ (742)

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

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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Amount of decrease 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 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 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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