Reconciliation of Total Amount of 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]
Balance, beginning of period	$ 30,005us-gaap_UnrecognizedTaxBenefits	$ 40,075us-gaap_UnrecognizedTaxBenefits	$ 76,818us-gaap_UnrecognizedTaxBenefits
Gross increases: tax positions taken in prior periods		515	8,380
Gross decreases: tax positions taken in prior periods	(1,040)	(13,042)	(8,943)
Gross increases: tax positions taken in current year	2,911	2,457	3,114
Gross decreases: tax positions taken in current year	0	0	0
Gross decreases: settlement of tax examinations			(39,294)
Gross decreases: lapse of statute of limitation	(1,487)
Balance, end of period	$ 30,389us-gaap_UnrecognizedTaxBenefits	$ 30,005us-gaap_UnrecognizedTaxBenefits	$ 40,075us-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

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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 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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