Valuation And Qualifying Accounts (Detail) - Allowance for doubtful accounts receivable - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of period		$ 5,339	$ 4,073	$ 4,975
Charged to costs and expenses		1,103	1,216	180
Charged to other accounts		0	0	0
Other	[1]	(1,139)	(520)	(960)
Balance at end of period		5,095	5,339	4,073
Foreign Currency Translation [Member]
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Cumulative translation adjustment		$ (208)	$ 570	$ (122)

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