Segment Information (Schedule Of Intercompany Sales By Geographic Area) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Intercompany sales	$ 156,362	$ 151,574	$ 467,028	$ 482,800
Intercompany Sales To Americas [Member]
Intercompany sales	16,551	15,361	52,831	49,631
Intercompany Sales To Germany [Member]
Intercompany sales	6,725	10,561	23,117	31,906
Intercompany Sales To Other EMEA [Member]
Intercompany sales	4,569	6,507	14,300	21,204
Intercompany Sales To Asia Pacific [Member]
Intercompany sales	8,533	6,400	22,211	20,575
Intercompany Sales [Member]
Intercompany sales	36,378	38,829	112,459	123,316
Americas [Member] | Intercompany Sales To Americas [Member]
Intercompany sales	733	1,160	2,011	2,480
Americas [Member] | Intercompany Sales To Germany [Member]
Intercompany sales	6,163	8,771	21,377	28,581
Americas [Member] | Intercompany Sales To Other EMEA [Member]
Intercompany sales	2,244	3,406	8,313	14,609
Americas [Member] | Intercompany Sales To Asia Pacific [Member]
Intercompany sales	6,322	4,583	15,882	13,025
Americas [Member] | Intercompany Sales [Member]
Intercompany sales	15,462	17,920	47,583	58,695
Germany [Member] | Intercompany Sales To Americas [Member]
Intercompany sales	240	171	3,604	377
Germany [Member] | Intercompany Sales To Other EMEA [Member]
Intercompany sales	976	1,919	2,254	3,812
Germany [Member] | Intercompany Sales To Asia Pacific [Member]
Intercompany sales	105		169
Germany [Member] | Intercompany Sales [Member]
Intercompany sales	1,321	2,090	6,027	4,189
Other EMEA [Member] | Intercompany Sales To Americas [Member]
Intercompany sales	14,972	13,320	44,946	44,634
Other EMEA [Member] | Intercompany Sales To Germany [Member]
Intercompany sales	562	1,790	1,740	3,325
Other EMEA [Member] | Intercompany Sales To Other EMEA [Member]
Intercompany sales	1,236	1,132	3,601	2,715
Other EMEA [Member] | Intercompany Sales To Asia Pacific [Member]
Intercompany sales	1,053	664	3,301	5,055
Other EMEA [Member] | Intercompany Sales [Member]
Intercompany sales	17,823	16,906	53,588	55,729
Asia Pacific [Member] | Intercompany Sales To Americas [Member]
Intercompany sales	606	710	2,270	2,140
Asia Pacific [Member] | Intercompany Sales To Other EMEA [Member]
Intercompany sales	113	50	132	68
Asia Pacific [Member] | Intercompany Sales To Asia Pacific [Member]
Intercompany sales	1,053	1,153	2,859	2,495
Asia Pacific [Member] | Intercompany Sales [Member]
Intercompany sales	$ 1,772	$ 1,913	$ 5,261	$ 4,703