v3.20.4

Investment in Loans (Schedule of Residential Mortgage Loans: Geographic Distribution) (Details) - Financing Receivables, Unpaid Principal Balance [Member] - Residential mortgage loans - Geographic Concentration Risk [Member] | 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%
CALIFORNIA |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Percentage of Total Outstanding Unpaid Principal Balance | 43.10% | 46.60%
Florida [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Percentage of Total Outstanding Unpaid Principal Balance | 14.80% | 11.90%
Texas [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Percentage of Total Outstanding Unpaid Principal Balance | 10.20% | 11.90%
Colorado [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Percentage of Total Outstanding Unpaid Principal Balance | 3.10% | 3.20%
MASSACHUSETTS |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Percentage of Total Outstanding Unpaid Principal Balance | 2.60% | 2.90%
MASSACHUSETTS |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Percentage of Total Outstanding Unpaid Principal Balance | 1.40% | 1.60%
NEVADA |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Percentage of Total Outstanding Unpaid Principal Balance | 1.90% | 1.60%
OREGON |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Percentage of Total Outstanding Unpaid Principal Balance | 2.20% | 2.20%
ARIZONA |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Percentage of Total Outstanding Unpaid Principal Balance | 2.00% | 2.40%
UTAH |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Percentage of Total Outstanding Unpaid Principal Balance | 1.70% | 1.90%
Maryland [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Percentage of Total Outstanding Unpaid Principal Balance | 1.60% | 1.30%
MARYLAND |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Percentage of Total Outstanding Unpaid Principal Balance | 1.00% | 1.10%
NORTH CAROLINA |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Percentage of Total Outstanding Unpaid Principal Balance | 1.10% | 0.80%
NEW JERSEY |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Percentage of Total Outstanding Unpaid Principal Balance | 1.40% | 1.10%
ILLINOIS |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Percentage of Total Outstanding Unpaid Principal Balance | 1.80% | 1.70%
Other [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Percentage of Total Outstanding Unpaid Principal Balance | 8.80% | 7.10%
GEORGIA |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Percentage of Total Outstanding Unpaid Principal Balance | 1.30% | 0.70%

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