Unrecognized Tax Benefits Excluding Interest Correlative Effects and Indirect Benefits (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Tax Disclosure [Abstract]
Unrecognized tax benefits at beginning of year	$ 11,826us-gaap_UnrecognizedTaxBenefits	$ 15,380us-gaap_UnrecognizedTaxBenefits	$ 9,288us-gaap_UnrecognizedTaxBenefits
Gross increases – tax positions in prior years	2,075	9,845	19,434
Gross decreases – tax positions in prior years	(203)	(5,121)	(13,876)
Gross increases – tax positions in current year	3,369	2,540	1,555
Gross decreases – tax positions in current year	(51)	(529)
Settlements with taxing authorities		(8,599)	(1,021)
Lapse of statute of limitations	(1,872)	(1,690)
Unrecognized tax benefits assumed with acquisition	5,963
Unrecognized tax benefits at end of year	$ 21,107us-gaap_UnrecognizedTaxBenefits	$ 11,826us-gaap_UnrecognizedTaxBenefits	$ 15,380us-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 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 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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