Income Taxes - Balance Sheet Classification of Net Deferred Income Tax Assets (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Abstract]
Current assets	$ 50,362	$ 60,143
Noncurrent assets	35,415us-gaap_DeferredTaxAssetsNetNoncurrent	35,623us-gaap_DeferredTaxAssetsNetNoncurrent
Noncurrent liabilities	(137,944)	(100,691)
Net deferred income tax asset (liability)	$ (52,167)us-gaap_DeferredTaxAssetsLiabilitiesNet	$ (4,925)us-gaap_DeferredTaxAssetsLiabilitiesNet

Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards, net of deferred tax liability attributable to taxable temporary differences.

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-Publisher FASB

-Name Accounting Standards Codification

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Amount after allocation of valuation allowances of noncurrent deferred tax asset attributable to deductible temporary differences and carryforwards. Noncurrent assets are expected to be realized or consumed after one year (or the normal operating cycle, if longer).

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

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Gross amount of noncurrent deferred tax liabilities, which result from applying the applicable tax rate to taxable temporary differences pertaining to each jurisdiction to which the entity is obligated to pay income tax.

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