Repurchase Agreements and Warehouse Facilities - Schedule of Unencumbered Securities (Details) $ in Thousands	Sep. 30, 2025 USD ($)
Assets Sold under Agreements to Repurchase [Line Items]
Securities borrowed	$ 459,633
Agency RMBS
Assets Sold under Agreements to Repurchase [Line Items]
Securities borrowed	423,418
Non-Agency RMBS
Assets Sold under Agreements to Repurchase [Line Items]
Securities borrowed	34,417
Non-Agency RMBS \| Consolidated SLST
Assets Sold under Agreements to Repurchase [Line Items]
Securities borrowed	11,900
U.S. Treasury securities
Assets Sold under Agreements to Repurchase [Line Items]
Securities borrowed	$ 1,798

Amount, after the effects of master netting arrangements, of securities borrowed from entities in exchange for collateral. Includes assets not subject to a master netting arrangement and not elected to be offset.

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 210
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-Name Accounting Standards Codification
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 210
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 210
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-Publisher FASB
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-URI https://asc.fasb.org/1943274/2147481420/860-30-50-1A

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