Tax Cuts and Jobs Act of 2017, accounting complete.

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

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Tax year that remains open to examination under enacted tax laws, in CCYY format.

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Income Taxes - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Contingency [Line Items]
Statutory corporate tax rate	21.00%	35.00%	35.00%
Tax cuts and jobs act of 2017, accounting complete	true
Unrecognized tax benefits	$ 0	$ 0	$ 0
Federal General Business Tax Credit Carry Forward [Member]
Income Tax Contingency [Line Items]
Tax credit carry forwards	0
Alternative Minimum Tax Credit Carry Forward [Member]
Income Tax Contingency [Line Items]
Tax credit carry forwards	0
State [Member]
Income Tax Contingency [Line Items]
Net operating loss carry forwards	$ 35,100,000
Net operating loss carry forwards expiration date	Dec. 31, 2025
Internal Revenue Service [Member]
Income Tax Contingency [Line Items]
Open tax years	2011 2012 2013 2014