Investments - Allowance for Credit Losses (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Finance Leases Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Financing Receivable, Individually Evaluated for Impairment	$ 38.4	$ 42.5
Notes Receivable [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Financing Receivable, Individually Evaluated for Impairment	$ 0.6	$ 3.5
Minimum [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Past Due Period Of Financing Receivable Accruing Interest	90 days