v3.20.4

Investment in Loans (Schedule of Commercial Loans: Geographic Distribution) (Details) - Financing Receivables, Unpaid Principal Balance [Member] - Geographic Concentration Risk [Member] - Commercial mortgage loans | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019
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 | 23.80% | 31.70%
NEW YORK |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Percentage of Total Outstanding Unpaid Principal Balance | 15.20% | 17.70%
Virginia [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Percentage of Total Outstanding Unpaid Principal Balance | 4.20% | 6.80%
CONNECTICUT |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Percentage of Total Outstanding Unpaid Principal Balance | 11.20% | 8.20%
MASSACHUSETTS |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Percentage of Total Outstanding Unpaid Principal Balance | 5.80% | 13.30%
NORTH CAROLINA |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Percentage of Total Outstanding Unpaid Principal Balance | 7.90% | 4.60%
CALIFORNIA |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Percentage of Total Outstanding Unpaid Principal Balance | 5.90% | 0.00%
MASSACHUSETTS |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Percentage of Total Outstanding Unpaid Principal Balance | 6.10% | 4.70%
ARIZONA |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Percentage of Total Outstanding Unpaid Principal Balance | 4.30% | 3.80%
Indiana [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Percentage of Total Outstanding Unpaid Principal Balance | 2.80% | 2.10%
PENNSYLVANIA |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Percentage of Total Outstanding Unpaid Principal Balance | 2.20% | 1.80%
NEVADA |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Percentage of Total Outstanding Unpaid Principal Balance | 1.90% | 1.50%
Tennessee [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Percentage of Total Outstanding Unpaid Principal Balance | 0.00% | 1.50%
ILLINOIS |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Percentage of Total Outstanding Unpaid Principal Balance | 1.40% | 1.20%
Other [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Percentage of Total Outstanding Unpaid Principal Balance | 0.00% | 1.10%
OHIO |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Percentage of Total Outstanding Unpaid Principal Balance | 7.30% | 0.00%

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