Income Taxes - Summary of Reconciliation between U.S. Statutory Federal Income Tax Rate and Effective Rate (Detail)	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Effective Income Tax Rate Continuing Operations Tax Rate Reconciliation [Abstract]
U.S. federal statutory rate	21.00%	34.00%
State income taxes, net of federal benefit	5.57%	4.67%
Federal rate change, deferred items	0.00%	(23.03%)
State rate change and other	(0.03%)	0.89%
Non-deductible interest	0.00%	(17.67%)
Federal NOLs to expire unutilized due to sec 382 limitation	0.00%	(14.02%)
Other permanent items	(0.98%)	(0.03%)
Change in valuation allowance	(25.56%)	15.19%
Effective rate	0.00%	0.00%

Effective income tax rate reconciliation nondeductible interest.

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to changes in the valuation allowance for deferred tax assets.

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