Segment Reporting (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022	Sep. 30, 2021
Operations of the Company's operating segments
Net Sales to External Customers	$ 982,117	$ 978,387	$ 1,910,855	$ 1,876,178
Revenue Transactions With Other Operating Segments	0	0	0	0
Net Sales	982,117	978,387	1,910,855	1,876,178
Segment Profit	307,704	285,432	574,155	526,677
Goodwill	665,100		665,100		$ 660,170	$ 643,449
Swiss Operations [Member]
Operations of the Company's operating segments
Net Sales to External Customers	46,803	42,062	93,172	85,331
Revenue Transactions With Other Operating Segments	181,073	210,449	383,207	404,284
Net Sales	227,876	252,511	476,379	489,615
Segment profit	66,914	72,012	143,336	143,334
Goodwill	25,865		25,865			22,634
Western European Operations [Member]
Operations of the Company's operating segments
Net Sales to External Customers	192,075	190,264	391,499	383,149
Revenue Transactions With Other Operating Segments	47,766	47,474	92,642	97,601
Net Sales	239,841	237,738	484,141	480,751
Segment profit	38,747	35,233	83,270	74,013
Goodwill	100,452		100,452			92,215
Chinese Operations [Member]
Operations of the Company's operating segments
Net Sales to External Customers	221,669	229,809	407,437	412,515
Revenue Transactions With Other Operating Segments	67,279	75,123	127,731	155,562
Net Sales	288,948	304,932	535,168	568,077
Segment profit	119,722	105,456	200,963	190,424
Goodwill	603		603			665
Other Operations [Member]
Operations of the Company's operating segments
Net Sales to External Customers	162,455	155,107	322,231	308,217
Revenue Transactions With Other Operating Segments	13,601	709	14,559	1,673
Net Sales	176,056	155,816	336,790	309,888
Segment profit	24,440	22,243	48,683	42,695
Goodwill	13,721		13,721			13,878
Intersegment Elimination [Member]
Operations of the Company's operating segments
Net Sales to External Customers	0	0	0	0
Revenue Transactions With Other Operating Segments	(343,460)	(374,069)	(685,128)	(739,007)
Net Sales	(343,460)	(374,069)	(685,128)	(739,007)
Segment profit	(46,325)	(42,308)	(88,097)	(91,771)
Goodwill	0		0			0
US Operations [Member]
Operations of the Company's operating segments
Net Sales to External Customers	359,115	361,145	696,516	686,966
Revenue Transactions With Other Operating Segments	33,741	40,314	66,989	79,887
Net Sales	392,856	401,459	763,505	766,854
Segment profit	104,206	$ 92,796	186,000	$ 167,982
Goodwill	$ 524,459		$ 524,459			$ 514,057