Loans (Loans on Non-accrual Status) (Parenthetical) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Jan. 01, 2020	Dec. 31, 2019
Finance Receivables Non Accrual Status By Type Of Holding [Line Items]
Interest on non-accrual loan	$ 0.4
Accrued interest reversed to non-accrual status	0.9
Non-accrual loans	381.8	$ 476.8	$ 326.3
Consumer Loans
Finance Receivables Non Accrual Status By Type Of Holding [Line Items]
Non-accrual loans	84.8	107.1	18.3
Consumer Loans | Legacy Consumer Mortgages
Finance Receivables Non Accrual Status By Type Of Holding [Line Items]
Non-accrual loans	77.8	$ 95.9	$ 14.3
Consumer Loans | Legacy Consumer Mortgages | PCD Loans
Finance Receivables Non Accrual Status By Type Of Holding [Line Items]
Non-accrual loans	$ 67.0