Summary of Significant Accounting Policies - Summary of Allowance for Doubtful Accounts Activity (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Accounting Policies [Abstract]
Allowance for doubtful accounts, Beginning Balance	$ 2,038	$ 2,007
Provision for doubtful accounts	2,149	1,825	$ 2,144
Write-offs, net of recoveries	(2,100)	(1,794)
Allowance for doubtful accounts, Ending Balance	$ 2,087	$ 2,038	$ 2,007