Goodwill and Other Intangible Assets (Schedule of Goodwill) (Details) $ in Thousands	6 Months Ended
Jun. 30, 2021 USD ($)
Goodwill [Roll Forward]
Beginning balance	$ 686,407
Goodwill written off related to spin-off of a business unit	(476)
Additions	18,260
Amortization of "second component" goodwill	(672)
Foreign currency translation	(1,068)
Ending balance	702,451
Domestic Operations
Goodwill [Roll Forward]
Beginning balance	333,502
Goodwill written off related to spin-off of a business unit	0
Additions	0
Amortization of "second component" goodwill	(672)
Foreign currency translation	0
Ending balance	332,830
International & Other
Goodwill [Roll Forward]
Beginning balance	352,905
Goodwill written off related to spin-off of a business unit	(476)
Additions	18,260
Amortization of "second component" goodwill	0
Foreign currency translation	(1,068)
Ending balance	$ 369,621

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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