Investments in Agency MBS - Additional Information About Gains and Losses Recognized with Respect to Investments in Agency MBS (Details) - Agency MBS - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Net gains (losses) recognized in earnings for:
MBS still held at period end	$ (24,430)	$ (2,904)	$ (26,911)	$ (13,323)
MBS sold during the period	1,702	457	(32,365)	(11,209)
Total	$ (22,728)	$ (2,447)	$ (59,276)	$ (24,532)

Amount of unrealized and realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in net income (trading).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 14
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Amount of realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in net income (trading).

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-Publisher FASB
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-Topic 220
-SubTopic 10
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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
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-Topic 320
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