Derivatives Long Positions in SOFR-based Interest Rate Swaptions (Details) - USD ($)	Sep. 30, 2025	Dec. 31, 2024
Interest Rate Swaption \| Long position
Derivative [Line Items]
Carrying Value	$ (286,000)
Carrying value	450,000	$ 0
Interest Rate Swaption \| Long position \| Not Designated as Hedging Instrument, Economic Hedge
Derivative [Line Items]
Cost	11,725,000
Fair Value	11,439,000
Notional Amount	$ 750,000,000	0
Average Fixed Receive Rate	3.25%
Exchange Traded Options \| Long position
Derivative [Line Items]
Fair Value		0
Exchange Traded Options \| Long position \| Not Designated as Hedging Instrument, Economic Hedge
Derivative [Line Items]
Cost	$ 8,008,000
Fair Value	7,500,000
Notional Amount	1,000,000,000	0
U.S. Treasury futures
Derivative [Line Items]
Fair Value		1,000,000
Carrying value	0
Interest rate swaps
Derivative [Line Items]
Fair Value	71,000,000	$ 153,000,000
Carrying value	$ 0

Derivative Instruments Not Designated as Hedging Instruments, Asset, at Cost Basis

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- Definition

Derivative Instruments Not Designated as Hedging Instruments, Carrying Value

+ References

No definition available.

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- Definition

Represents the fair value of the instrument, net of its cost not yet paid.

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No definition available.

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- Definition

Fair value as of the balance sheet date of derivative instrument not designated as hedging instrument and classified as an asset.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Nominal or face amount used to calculate payment on derivative.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-Section 50
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- Definition

Fixed interest rate that will be received or paid upon exercise of the interest rate swaption contract.

+ References

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