Income Taxes - Additional Information (Detail) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Operating Loss Carryforwards [Line Items]
Deferred tax assets valuation allowance	$ 132,646,000	$ 119,349,000
Cumulative loss period	3 years
Deferred tax (liability) asset, net	(1,514,000)us-gaap_DeferredTaxAssetsLiabilitiesNet	4,575,000us-gaap_DeferredTaxAssetsLiabilitiesNet
Tax expense relating to the deferred tax liability	1,313,000us-gaap_DeferredIncomeTaxExpenseBenefit	297,000us-gaap_DeferredIncomeTaxExpenseBenefit
Uncertain tax liability	0	0
Unrecognized tax benefits	0us-gaap_UnrecognizedTaxBenefits	0us-gaap_UnrecognizedTaxBenefits
Federal [Member]
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	264,300,000
Federal [Member] \| Expiry 2030 [Member]
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	38,400,000
Net Operating Loss Carryforward Expiration Year	2030
Federal [Member] \| Expiry 2031 [Member]
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	112,500,000
Net Operating Loss Carryforward Expiration Year	2031
Federal [Member] \| Expiry 2032 [Member]
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	50,000,000
Net Operating Loss Carryforward Expiration Year	2032
Federal [Member] \| Expiry 2033 [Member]
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	25,700,000
Net Operating Loss Carryforward Expiration Year	2033
Federal [Member] \| Expiry 2034 [Member]
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	37,700,000
Net Operating Loss Carryforward Expiration Year	2034
State [Member]
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	326,500,000
State [Member] \| Expiry 2030 [Member]
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	74,700,000
State [Member] \| Expiry 2031 [Member]
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	109,800,000
State [Member] \| Expiry 2032 [Member]
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	45,200,000
State [Member] \| Expiry 2033 [Member]
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	22,300,000
State [Member] \| Expiry 2034 [Member]
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	34,100,000
State [Member] \| Expiry 2015 [Member]
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	3,000,000
State [Member] \| Expiry 2029 [Member]
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	$ 37,430,000

Cumulative loss period.

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Net operating loss carryforward expiration year.

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Amount of deferred income tax expense (benefit) pertaining to income (loss) from continuing operations.

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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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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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

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Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

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