Revenue (Disaggregation of revenue) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Disaggregation Of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	$ 533,005	$ 623,427
Operating Segments [Member]
Disaggregation Of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	514,964	602,820
Operating Segments [Member] | Industrials Sector [Member]
Disaggregation Of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	102,826	116,373
Operating Segments [Member] | Aerospace And Defense Sector [Member]
Disaggregation Of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	119,200	103,889
Operating Segments [Member] | Medical Sector [Member]
Disaggregation Of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	117,976	103,478
Operating Segments [Member] | Semi-Cap Sector [Member]
Disaggregation Of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	82,720	66,021
Operating Segments [Member] | Computing Sector [Member]
Disaggregation Of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	36,601	124,310
Operating Segments [Member] | Telecommunications Sector [Member]
Disaggregation Of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	55,641	88,749
Elimination Of Intersegment Sales [Member]
Disaggregation Of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	18,041	20,607
Americas [Member]
Disaggregation Of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	314,396	392,058
Americas [Member] | Operating Segments [Member]
Disaggregation Of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	303,508	378,956
Americas [Member] | Operating Segments [Member] | Industrials Sector [Member]
Disaggregation Of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	33,945	42,767
Americas [Member] | Operating Segments [Member] | Aerospace And Defense Sector [Member]
Disaggregation Of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	113,012	96,337
Americas [Member] | Operating Segments [Member] | Medical Sector [Member]
Disaggregation Of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	69,379	58,411
Americas [Member] | Operating Segments [Member] | Semi-Cap Sector [Member]
Disaggregation Of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	30,449	28,400
Americas [Member] | Operating Segments [Member] | Computing Sector [Member]
Disaggregation Of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	30,074	110,268
Americas [Member] | Operating Segments [Member] | Telecommunications Sector [Member]
Disaggregation Of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	26,649	42,773
Americas [Member] | Elimination Of Intersegment Sales [Member]
Disaggregation Of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	10,888	13,102
Asia [Member]
Disaggregation Of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	171,609	187,409
Asia [Member] | Operating Segments [Member]
Disaggregation Of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	164,906	180,049
Asia [Member] | Operating Segments [Member] | Industrials Sector [Member]
Disaggregation Of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	48,225	55,582
Asia [Member] | Operating Segments [Member] | Aerospace And Defense Sector [Member]
Disaggregation Of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	0	0
Asia [Member] | Operating Segments [Member] | Medical Sector [Member]
Disaggregation Of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	44,203	40,459
Asia [Member] | Operating Segments [Member] | Semi-Cap Sector [Member]
Disaggregation Of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	37,292	24,743
Asia [Member] | Operating Segments [Member] | Computing Sector [Member]
Disaggregation Of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	6,527	14,009
Asia [Member] | Operating Segments [Member] | Telecommunications Sector [Member]
Disaggregation Of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	28,659	45,256
Asia [Member] | Elimination Of Intersegment Sales [Member]
Disaggregation Of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	6,703	7,360
Europe [Member]
Disaggregation Of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	47,000	43,960
Europe [Member] | Operating Segments [Member]
Disaggregation Of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	46,550	43,815
Europe [Member] | Operating Segments [Member] | Industrials Sector [Member]
Disaggregation Of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	20,656	18,024
Europe [Member] | Operating Segments [Member] | Aerospace And Defense Sector [Member]
Disaggregation Of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	6,188	7,552
Europe [Member] | Operating Segments [Member] | Medical Sector [Member]
Disaggregation Of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	4,394	4,608
Europe [Member] | Operating Segments [Member] | Semi-Cap Sector [Member]
Disaggregation Of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	14,979	12,878
Europe [Member] | Operating Segments [Member] | Computing Sector [Member]
Disaggregation Of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	0	33
Europe [Member] | Operating Segments [Member] | Telecommunications Sector [Member]
Disaggregation Of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	333	720
Europe [Member] | Elimination Of Intersegment Sales [Member]
Disaggregation Of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	$ 450	$ 145