Summary of Significant Accounting Policies - Schedule of Allowances Against Accounts and Notes Receivable (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Receivables [Abstract]
Balance at beginning of period	$ 4,495	$ 4,122	$ 3,913
Additions/ charges to cost and expense for allowances for doubtful accounts	433	630	604
Adjustments (to)/from deferred revenue, net, for accounts where collectability is remote	(80)	228	(160)
Deductions/ write-offs	(365)	(485)	(235)
Balance at end of period	$ 4,483	$ 4,495	$ 4,122