Income Taxes - Variations from Federal Statutory Rate (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Expected federal income tax expense (benefit) at statutory rate of 34%	$ (5,755)	$ (3,068)	$ (3,348)
Effect of permanent other differences	212	44
Difference in basis for sale of discontinued operations	(347)
State income tax benefit, net of federal benefit tax assets	(254)	(135)	(148)
Valuation allowance		3,156	$ 3,496
Total income tax benefit	$ (6,144)	$ (3)