Intangible Assets and Goodwill (Intangible Assets) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Finite lived intangible assets
Gross Carrying Amount	$ 287,199	$ 310,589
Accumulated Amortization	(127,360)	(119,949)
Net Carrying Amount	159,839	190,640
Amortization expense	33,000	36,000	$ 39,000
Customer relationships
Finite lived intangible assets
Gross Carrying Amount	268,199	265,665
Accumulated Amortization	(115,010)	(88,550)
Net Carrying Amount	153,189	177,115
Software & technology
Finite lived intangible assets
Gross Carrying Amount	19,000	31,600
Accumulated Amortization	(12,350)	(19,999)
Net Carrying Amount	6,650	11,601
Trademarks & other
Finite lived intangible assets
Gross Carrying Amount	0	13,324
Accumulated Amortization	0	(11,400)
Net Carrying Amount	$ 0	$ 1,924