Income Taxes - Narrative (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Federal income tax expense (benefit)	$ 0.0	$ 0.0
State income tax expense (benefit), continuing operationsi	$ 0.0	$ 0.0
Statutory tax (benefit) expense	21.00%	21.00%
Operating loss carryforwards	$ 337.0
Operating loss carryforwards, not subject to expiration	$ 34.0

Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards that are not subject to expiration dates.

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

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Amount of current and deferred federal income tax expense (benefit) attributable to income (loss) from continuing operations.

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Amount of state and local current and deferred income tax expense (benefit) attributable to continuing operations.

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