Schedule Of Changes In 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 at January 1, 2014	$ 2,312us-gaap_UnrecognizedTaxBenefits
Increase related to positions taken in prior period	938
Increase related to positions taken in current period	270
Decrease related to expiration of statute of limitations	(60)
Unrecognized tax benefits at December 31, 2014	3,460us-gaap_UnrecognizedTaxBenefits
Accrued interest	292	300
Netting of deferred tax assets and unrecognized tax benefits	(1,273)
Unrecognized tax benefits recorded in other long-term liabilities at December 31, 2014	$ 2,479

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Amount of decrease in unrecognized tax benefits resulting from netting against deferred tax assets.

+ References

No definition available.

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- Definition

The noncurrent portion of the amount recognized for uncertain tax positions as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.24)

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- Definition

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

-URI http://asc.fasb.org/extlink&oid=6527854

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-Name Accounting Standards Codification

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-Section 50

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- Definition

Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

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- Definition

Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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-Topic 740

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- Definition

Amount of interest expense accrued for an underpayment of income taxes.

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-Topic 740

-SubTopic 10

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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

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-Topic 740

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