Organization and Significant Accounting Policies - Allowance for Doubtful Accounts (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Allowance for Doubtful Accounts Receivable [Roll Forward]
Balance at January 1	$ 1,772	$ 1,922	$ 1,189
Provision charged to expense	172	0	1,099
Write-offs / Recoveries	(375)	(150)	(366)
Balance at December 31	$ 1,569	$ 1,772	$ 1,922