Other Assets - Other Assets (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Other Assets Non Current [Line Items]
Capitalized software, net of amortization	$ 3,678us-gaap_CapitalizedComputerSoftwareNet	$ 5,472us-gaap_CapitalizedComputerSoftwareNet
Deferred loan costs, net of amortization	608	288
Other non-current assets	348	321
Total other assets	30,349us-gaap_OtherAssetsNoncurrent	30,991us-gaap_OtherAssetsNoncurrent
Rabbi Trust [Member]
Other Assets Non Current [Line Items]
Assets held in Rabbi Trust	$ 25,715	$ 24,910

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The amount of cash, securities, or other assets held by a third-party trustee pursuant to the terms of an agreement which assets are available to be used by beneficiaries to that agreement only within the specific terms thereof and which agreement is expected to terminate more than one year from the balance sheet date (or operating cycle, if longer) at which time the assets held-in-trust will be released or forfeited.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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- Definition

The carrying amount of capitalized computer software costs net of accumulated amortization as of the balance sheet date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 985

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- Definition

Net amount of long-term deferred finance costs capitalized at the end of the reporting period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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-Publisher FASB

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Amount of other miscellaneous assets expected to be realized or consumed after one year or normal operating cycle, if longer.

+ References

No definition available.

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Aggregate carrying amount, as of the balance sheet date, of noncurrent assets not separately disclosed in the balance sheet. Noncurrent assets are expected to be realized or consumed after one year (or the normal operating cycle, if longer).

+ References

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-Publisher FASB

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