Income Taxes - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Line Items]
Unrecognized tax benefits	$ 0	$ 0
State [Member]
Income Tax Disclosure [Line Items]
Tax credit carry forwards	868,000
Federal General Business Tax Credit Carry Forward [Member]
Income Tax Disclosure [Line Items]
Tax credit carry forwards	0
Alternative Minimum Tax Credit Carry Forward [Member]
Income Tax Disclosure [Line Items]
Tax credit carry forwards	$ 1,600,000
Capital Loss Carry Forward [Member]
Income Tax Disclosure [Line Items]
Tax credit carry forwards expiration date	Dec. 31, 2025