Financing Activity - Carrying and Fair Values of Mortgage Loans (Parenthetical) (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Mortgage Loan
Debt Instrument [Line Items]
Debt issuance costs, line of credit arrangements	$ 0.5	$ 2.1

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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+ Details