Schedule II - Valuation and Qualifying Accounts (Detail) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2015		Dec. 31, 2014		Dec. 31, 2013
Allowance for doubtful receivables
Movement in Valuation Allowances and Reserves [Roll Forward]
Beginning of Period		$ 709	[1]	$ 480	[1]	$ 469
Charges to Costs and Expenses		855		384		60
Charges (Deductions) to Other Accounts	[2]	(53)		(39)		15
Deductions		(260)	[2]	(116)	[1]	(64)	[2]
End of Period	[1]	1,251		709		480
Tax valuation allowances
Movement in Valuation Allowances and Reserves [Roll Forward]
Beginning of Period		3,727	[3]	3,315	[3]	3,587
Charges to Costs and Expenses		1,615		1,120		855
Charges (Deductions) to Other Accounts		(272)	[2],[4]	193		0
Deductions		(763)	[2],[5]	(901)		(1,127)	[3]
End of Period	[3]	$ 4,307		$ 3,727		$ 3,315

[1] Uncollected receivables written off and recoveries.

[2] Foreign currency translation and other adjustments.

[3] Reduction to income tax expense.

[4] Adjustments relating to the acquisition of Industrial Filtration.

[5] Adjustments relating to the acquisition of Industrial Filtration.