Income tax.

No definition available.

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Amount of current federal 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.

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- Definition

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

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- Definition

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

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

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Income Tax - Additional Information (Detail) - USD ($)	9 Months Ended	12 Months Ended
Income Tax - Additional Information (Detail) - USD ($)	Sep. 30, 2019	Dec. 31, 2019	Dec. 31, 2017
Income Tax [Line Items]
U.S. statutory tax rate	21.00%		35.00%
Scenario, Forecast [Member]
Income Tax [Line Items]
Percentage of annual effective income tax rate		0.00%
Current federal income tax anticipated to be paid		$ 0
Net deferred tax asset		0
Net income tax expense or benefit		$ 0