Retirement Plans - Summary of 401(k) Contribution Plan (Detail) - 401(k) Plan [Member] - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Defined Contribution Plan Disclosure [Line Items]
401(k) Plan benefits expense	$ 187	$ 150	$ 515	$ 150
401(k) Plan contributions made by the Company	$ 187		$ 648