Principal Repayments on Term Loan Outstanding (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013
Long Term Debt Maturities Repayments Of Principal [Line Items]
2014	$ 7,500
2015	7,500
2016	7,500
2017	20,000
Total debt repayments	$ 42,500

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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 16

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

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-Topic 210

-SubTopic 10

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-Paragraph 1

-Subparagraph (SX 210.5-02.22)

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-Number 210

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-Paragraph 20, 22

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the next fiscal year following the latest fiscal year.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 470

-SubTopic 10

-Section 50

-Paragraph 1

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the fourth fiscal year following the latest fiscal year.

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the third fiscal year following the latest fiscal year.

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the second fiscal year following the latest fiscal year.

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