Summary of Significant Accounting Policies - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2016 USD ($)
Summary Of Significant Accounting Policies [Line Items]
Cumulative effect change in stockholders' equity	$ 646,031
ASU 2016-09 [Member]
Summary Of Significant Accounting Policies [Line Items]
Additional non-current deferred tax asset amount	657,000
Cumulative effect change in stockholders' equity	$ 28,000