v3.21.2

Investment in Loans (Schedule of Commercial Loans: Geographic Distribution) (Details) - Geographic Concentration Risk [Member] - Commercial mortgage loans - Financing Receivables, Unpaid Principal Balance [Member] | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2021 | Dec. 31, 2020
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Percentage of Total Outstanding Unpaid Principal Balance | 100.00% | 100.00%
Florida [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Percentage of Total Outstanding Unpaid Principal Balance | 26.60% | 23.80%
NEW YORK |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Percentage of Total Outstanding Unpaid Principal Balance | 20.20% | 15.20%
Virginia [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Percentage of Total Outstanding Unpaid Principal Balance | 0.00% | 4.20%
CONNECTICUT |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Percentage of Total Outstanding Unpaid Principal Balance | 7.00% | 11.20%
MASSACHUSETTS |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Percentage of Total Outstanding Unpaid Principal Balance | 5.00% | 5.80%
NORTH CAROLINA |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Percentage of Total Outstanding Unpaid Principal Balance | 6.80% | 7.90%
CALIFORNIA |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Percentage of Total Outstanding Unpaid Principal Balance | 4.70% | 5.90%
MASSACHUSETTS |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Percentage of Total Outstanding Unpaid Principal Balance | 0.00% | 6.10%
ARIZONA |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Percentage of Total Outstanding Unpaid Principal Balance | 6.20% | 4.30%
Indiana [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Percentage of Total Outstanding Unpaid Principal Balance | 2.30% | 2.80%
PENNSYLVANIA |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Percentage of Total Outstanding Unpaid Principal Balance | 5.70% | 2.20%
NEVADA |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Percentage of Total Outstanding Unpaid Principal Balance | 1.50% | 1.90%
ILLINOIS |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Percentage of Total Outstanding Unpaid Principal Balance | 0.00% | 1.40%
OHIO |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Percentage of Total Outstanding Unpaid Principal Balance | 5.90% | 7.30%
MICHIGAN |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Percentage of Total Outstanding Unpaid Principal Balance | 4.70% | 0.00%
NEW HAMPSHIRE |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Percentage of Total Outstanding Unpaid Principal Balance | 3.40% | 0.00%

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