Information on Business Segments (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
	Mar. 31, 2012 Segment	Dec. 31, 2012 Segment	Dec. 31, 2011	Dec. 31, 2010
Segment Reporting Information [Line Items]
Number Of Reportable Segments	3	3
Revenues		$ 1,229,959	$ 1,169,355	$ 1,028,617
Operating profit		136,556	127,555	86,398
Assets		1,868,596	1,440,365	1,403,257
Depreciation and amortization		57,360	58,904	52,770
Capital expenditures		37,787	37,082	28,759
Interest expense		12,238	10,271	19,984
Other expense (income), net		2,671	395	2,609
Income from continuing operations before income taxes		121,647	116,889	63,805
General Electric [Member]
Segment Reporting Information [Line Items]
Entity-Wide Revenue, Major Customer, Percent		17.00%	19.00%	20.00%
Aerospace [Member]
Segment Reporting Information [Line Items]
Revenues		390,483	382,506	334,180
Operating profit		63,251	62,647	52,415
Assets		533,465	544,953	545,212
Depreciation and amortization		21,161	24,191	20,757
Capital expenditures		8,554	13,459	9,857
Industrial [Member]
Segment Reporting Information [Line Items]
Revenues		497,043	440,482	374,068
Operating profit		43,914	39,094	29,366
Assets		876,946	453,279	436,794
Depreciation and amortization		23,799	18,767	16,275
Capital expenditures		23,835	18,615	11,736
Distribution [Member]
Segment Reporting Information [Line Items]
Revenues		350,739	355,262	329,518
Operating profit		29,391	25,814	4,617
Assets		272,871	278,139	341,092
Depreciation and amortization		10,270	13,548	13,610
Capital expenditures		5,035	4,674	6,858
Other [Member]
Segment Reporting Information [Line Items]
Revenues		(8,306)	(8,895)	(9,149)
Operating profit		0	0	0
Assets		185,314	164,004	80,159
Depreciation and amortization		2,130	2,398	2,138
Capital expenditures		$ 363	$ 334	$ 328