Schedule II - Valuation and Qualifying Accounts (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Year	$ 1,120	$ 1,635	$ 826
Additions, Charged to Income	979	1,073	1,796
Additions, Other Accounts	246	85	249
Deductions	(1,436)	(1,673)	(1,236)
Balance at End of Year	$ 909	$ 1,120	$ 1,635