Summary of Financial Information by Reportable Segment (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended				6 Months Ended
	Jun. 30, 2012		Jun. 30, 2011		Jun. 30, 2012		Jun. 30, 2011
Segment Reporting Information [Line Items]
Revenues	$ 613,014		$ 610,693		$ 1,217,370		$ 1,142,546
Operating income	108,035		99,172		187,827		185,995
Interest expense	3,967		3,934		7,801		9,281
Other income, net	(357)		279		(1,580)		(683)
Consolidated income before income taxes	104,425		94,959		181,606		177,397
Industrial Products Group
Segment Reporting Information [Line Items]
Revenues	329,722		327,846		655,549		614,056
Operating income	40,825	[1]	34,325	[1]	56,364	[1]	65,127	[1]
Operating income as a percentage of revenues	12.40%		10.50%		8.60%		10.60%
Engineered Products Group
Segment Reporting Information [Line Items]
Revenues	283,292		282,847		561,821		528,490
Operating income	$ 67,210	[1]	$ 64,847	[1]	$ 131,463	[1]	$ 120,868	[1]
Operating income as a percentage of revenues	23.70%		22.90%		23.40%		22.90%

[1] See Note 3 "Restructuring."