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Mortgage-Backed Securities - Unrealized Gain (Loss) on Investments (Details) - USD ($) $ in Thousands | 3 Months Ended
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Mar. 31, 2023 | Mar. 31, 2022
Investments [Line Items] |  |
Unrealized gain (loss) on investments, net | $ 57,120 | $ (111,251)
Residential Mortgage Backed Securities [Member] |  |
Investments [Line Items] |  |
Debt Securities, Trading, Unrealized Gain (Loss) | 55,779 | (110,201)
Commercial Mortgage Backed Securities [Member] |  |
Investments [Line Items] |  |
Debt Securities, Trading, Unrealized Gain (Loss) | 237 | 0
Interest-Only-Strip [Member] |  |
Investments [Line Items] |  |
Debt Securities, Trading, Unrealized Gain (Loss) | 1,092 | (1,130)
Asset-backed Securities, Securitized Loans and Receivables |  |
Investments [Line Items] |  |
Unrealized gain (loss) on other investments | $ 12 | $ 80

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- Definition Unrealized gain (loss) on other investments resulting from change in fair value during the period recorded within net income. + References No definition available. + Details
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- Definition Amount of unrealized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in net income (trading). + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (e) -URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27357-111563 + Details
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- Definition Amount of unrealized gain (loss) on investment. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3602-108585 + Details
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