Income Taxes - Additional Information (Detail) - USD ($)	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Income Tax Disclosure [Abstract]
Income tax expense	$ 406,000	$ 341,000
Pre-tax loss	5,720,000	4,072,000
Income tax benefit recognized with respect to losses incurred	0
Income tax expense with respect to earnings	0
Increase or decrease in unrecognized tax benefits	0
Interest or penalties associated with uncertain tax positions	$ 0	$ 0