Valuation And Qualifying Accounts (Detail) - Allowance for doubtful accounts receivable - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of period		$ 4,975	$ 5,497	$ 5,717
Charged to costs and expenses		180	309	1,871
Charged to other accounts		0	0	0
Other	[1]	(960)	(462)	(1,702)
Balance at end of period		4,073	4,975	5,497
Foreign Currency Translation [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Cumulative translation adjustment		$ (122)	$ (369)	$ (389)

[1] Uncollectible accounts written off, net of recoveries.