Goodwill and Intangible Assets Goodwill Rollforward (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Goodwill
Goodwill	$ 695,044	$ 550,202	$ 359,688
Addition due to acquisition	146,121	193,389
Purchase accounting adjustments	451
Other, including foreign currency translation	(1,730)	(2,875)
SCEM
Goodwill
Goodwill	397,952	301,423	304,270
Addition due to acquisition	98,410	0
Purchase accounting adjustments	0
Other, including foreign currency translation	(1,881)	(2,847)
MC
Goodwill
Goodwill	240,021	191,708	8,007
Addition due to acquisition	47,711	183,729
Purchase accounting adjustments	451
Other, including foreign currency translation	151	(28)
AMH
Goodwill
Goodwill	57,071	57,071	$ 47,411
Addition due to acquisition	0	9,660
Purchase accounting adjustments	0
Other, including foreign currency translation	$ 0	$ 0

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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