Fair Values - (Carrying Value and Fair Value of Financial Instruments) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Carrying Value
Book and estimated fair values of financial instruments
Net investment in leases	$ 43.0
Loans receivable and other lending investments	333.0	$ 687.0
Loans receivable held for sale	43.0
Cash and cash equivalents	340.0	99.0
Restricted cash	54.0	52.0
Loan participations payable, net		43.0
Debt obligations, net	2,572.0	2,569.0
Carrying Value \| Fair Value, Inputs, Level 1
Book and estimated fair values of financial instruments
Debt obligations, net	2,473.0	2,471.0
Carrying Value \| Fair Value, Inputs, Level 3
Book and estimated fair values of financial instruments
Debt obligations, net	99.0	98.0
Fair Value
Book and estimated fair values of financial instruments
Net investment in leases	43.0
Loans receivable and other lending investments	345.0	726.0
Loans receivable held for sale	43.0
Cash and cash equivalents	340.0	99.0
Restricted cash	54.0	52.0
Loan participations payable, net		43.0
Debt obligations, net	2,903.0	2,683.0
Fair Value \| Fair Value, Inputs, Level 1
Book and estimated fair values of financial instruments
Debt obligations, net	2,799.0	2,581.0
Fair Value \| Fair Value, Inputs, Level 3
Book and estimated fair values of financial instruments
Debt obligations, net	$ 104.0	$ 102.0
3.125% Senior Convertible Notes
Book and estimated fair values of financial instruments
Stated interest rate	3.125%
3.125% Senior Convertible Notes \| Unsecured notes
Book and estimated fair values of financial instruments
Stated interest rate	3.125%	3.125%
3.125% Senior Convertible Notes \| Unsecured notes \| Fair Value, Inputs, Level 1
Book and estimated fair values of financial instruments
Debt obligations, net	$ 527.5	$ 338.8

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- Definition

Sales Type Lease, Lease Receivable, Fair Value Disclosure

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- Definition

Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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- Definition

Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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Fair value portion of contractual obligation to pay money on demand or on fixed or determinable dates.

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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

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