Reconciliations of Total Amount of Gross Unrecognized Tax Benefits (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Schedule of Unrecognized Tax Benefits [Line Items]
Unrecognized Tax Benefits, Increase Resulting from Acquisition	$ 2,431	$ 0
Gross unrecognized tax benefits at beginning of year	4,277us-gaap_UnrecognizedTaxBenefits	5,419us-gaap_UnrecognizedTaxBenefits
Increases in tax positions for prior years	0	28
Decreases in tax positions for prior years	(246)	0
Increases in tax positions for current year	2,409	1,879
Settlements	(1,385)	(2,298)
Lapse in statute of limitations	(1,502)	(751)
Gross unrecognized tax benefits at end of year	$ 5,984us-gaap_UnrecognizedTaxBenefits	$ 4,277us-gaap_UnrecognizedTaxBenefits

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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 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 acquisitions.

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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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