Income Taxes - Reconciliation Of Changes In Unrecognized Tax Benefits (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Unrecognized tax benefits at January 1,	$ 4,648us-gaap_UnrecognizedTaxBenefits	$ 12,303us-gaap_UnrecognizedTaxBenefits
Increases for positions taken during current period	1,074	758
Increases for positions taken during prior periods	62	333
Decreases for positions taken during prior periods	(438)	(4,939)
Acquired unrecognized tax benefits	1,374	0
Lapse of statute of limitations	(8)	(3,580)
Settlements with taxing authorities	(28)	(227)
Unrecognized tax benefits at December 31,	$ 6,684us-gaap_UnrecognizedTaxBenefits	$ 4,648us-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

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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 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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