Investments - Schedule of Loan Exit Fees Receivable (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Exit Fees Receivable	$ 37.6	$ 37.5
Included in Cost
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Exit Fees Receivable	34.7	32.5
Deferred Fees
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Exit Fees Receivable	$ 2.9	$ 5.0