Financing Receivables - Schedule of Financing Receivable Past Due (Details) - PSAs - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Financing Receivable, Past Due [Line Items]
Past due financing receivables	$ 12.5	$ 12.8
Total not considered past due	305.7	314.7
Total	318.2	327.5
Greater than 90 days past due and accruing interest	7.2	7.2
30-59 days past due
Financing Receivable, Past Due [Line Items]
Past due financing receivables	3.5	3.7
60-90 days past due
Financing Receivable, Past Due [Line Items]
Past due financing receivables	1.8	1.9
Greater than 90 days past due
Financing Receivable, Past Due [Line Items]
Past due financing receivables	$ 7.2	$ 7.2