Business Segments (Principal Geographical Areas) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Principal Geographical Areas Information
Revenue from external customers	$ 4,641,830	$ 5,318,763	$ 4,450,832
Assets	4,724,898	5,045,617
United States
Principal Geographical Areas Information
Revenue from external customers	4,267,734	4,953,045	4,073,691
Assets	4,479,873	4,836,735
Foreign and U.S. Territories
Principal Geographical Areas Information
Revenue from external customers	374,096	365,718	$ 377,141
Assets	$ 245,025	$ 208,882