Debt (Summary of Term ABS Financings) (Details) $ in Millions	3 Months Ended
	Mar. 31, 2020 USD ($)
Term ABS 2017-1 [Member]
Debt Instrument [Line Items]
Close Date	Feb. 23, 2017
Net Book Value of Loans Contributed at Closing	$ 437.8
Maturity Date	Feb. 15, 2019	[1],[2]
Term ABS 2017-2 [Member]
Debt Instrument [Line Items]
Close Date	Jun. 29, 2017
Net Book Value of Loans Contributed at Closing	$ 563.2
Maturity Date	Jun. 17, 2019	[1],[2]
Term ABS 2017-3 [Member]
Debt Instrument [Line Items]
Close Date	Oct. 26, 2017
Net Book Value of Loans Contributed at Closing	$ 437.6
Maturity Date	Oct. 15, 2019	[1],[2]
Term ABS 2018-1 [Member]
Debt Instrument [Line Items]
Close Date	Feb. 22, 2018
Net Book Value of Loans Contributed at Closing	$ 625.1
Maturity Date	Feb. 17, 2020	[1],[2]
Term ABS 2018-2 [Member]
Debt Instrument [Line Items]
Close Date	May 24, 2018
Net Book Value of Loans Contributed at Closing	$ 562.6
Maturity Date	May 15, 2020	[1],[2]
Term ABS 2018-3 [Member]
Debt Instrument [Line Items]
Close Date	Aug. 23, 2018
Net Book Value of Loans Contributed at Closing	$ 500.1
Maturity Date	Aug. 17, 2020	[1],[2]
Term ABS 2019-1 [Member]
Debt Instrument [Line Items]
Close Date	Feb. 21, 2019
Net Book Value of Loans Contributed at Closing	$ 503.1
Maturity Date	Feb. 15, 2021	[1],[2]
Term ABS 2019-2 [Member]
Debt Instrument [Line Items]
Close Date	Aug. 28, 2019
Net Book Value of Loans Contributed at Closing	$ 625.1
Maturity Date	Aug. 15, 2022	[1],[3]

[1] Financing made available only to a specified subsidiary of the Company.

[2] Represents the revolving maturity date. The outstanding balance will amortize after the revolving maturity date based on the cash flows of the pledged assets.

[3] Represents the revolving maturity date. The Company has the option to redeem and retire the indebtedness after the revolving maturity date. If we do not elect this option, the outstanding balance will amortize based on the cash flows of the pledged assets.