Income Taxes - Components of the Net Deferred Tax Assets (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Abstract]
Assets, Current	$ 1,265us-gaap_DeferredTaxAssetsGrossCurrent	$ 1,238us-gaap_DeferredTaxAssetsGrossCurrent
Liabilities, Current	(3)	(4)
Valuation allowance, Current	(66)	(59)
Net deferred tax asset (liability), Current	1,196	1,175
Assets, Long-term	27,677	30,625
Liabilities, Long-term	(269)	(87)
Valuation allowance, Long-term	(1,434)	(1,441)
Net deferred tax asset (liability), Long-term	$ 25,974	$ 29,097

Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards expected to be realized or consumed within one year or operating cycle, if longer.

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized expected to be realized or consumed after one year (or the normal operating cycle, if longer).

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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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