Other Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Impaired Long-Lived Assets Held and Used [Line Items]
Machinery and Equipment, Gross	$ 11,182	$ 10,432
Furniture and Fixtures, Gross	11,019	10,768
Other Purchased Software, Gross	1,992	4,527
Property, Plant and Equipment, Other, Gross	53	171
Leasehold Improvements, Gross	29,543	27,701
Property, Plant and Equipment, Gross	53,789	53,599
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	(37,939)	(30,765)
Property, Plant and Equipment, Net	15,850	22,834
Capitalized Computer Software, Gross	55,943	36,795
Capitalized Computer Software, Accumulated Amortization	(28,524)	(18,456)
Capitalized Computer Software, Net	27,419	18,339
Accounts Receivable from Securitization	0	5,136
Prepaid Expense	17,241	12,217
Deferred Income Tax Assets, Net	1,716	1,563
Other Assets, Miscellaneous	18,305	16,682
Other Assets	80,531	76,771
Depreciation	9,400	8,800
Capitalized Computer Software, Amortization	10,800	4,900
Capitalized Computer Software, Additions	21,700	$ 17,900
Software and Software Development Costs [Member]
Impaired Long-Lived Assets Held and Used [Line Items]
Asset Impairment Charges	1,800
Property, Plant and Equipment [Member]
Impaired Long-Lived Assets Held and Used [Line Items]
Asset Impairment Charges	$ 1,900