Mortgage-Backed Securities - Collateral Characteristics of Non-Agency Residential MBS (Details) - Non-Agency RMBS - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Debt Securities, Available-for-sale [Line Items]
Weighted average maturity (years)	15 years 7 months 6 days	16 years 3 months 18 days
Weighted average amortized loan to value	53.80%	54.50%
Weighted average FICO	707	707
Weighted average loan balance (in thousands)	$ 239	$ 243
Weighted average percentage owner-occupied	69.40%	68.70%
Weighted average percentage single family residence	60.50%	60.40%
Weighted average current credit enhancement	0.60%	0.70%
CA
Debt Securities, Available-for-sale [Line Items]
Weighted average geographic concentration of top four states	33.60%	33.50%
NY
Debt Securities, Available-for-sale [Line Items]
Weighted average geographic concentration of top four states	12.50%	12.30%
FL
Debt Securities, Available-for-sale [Line Items]
Weighted average geographic concentration of top four states	7.10%	7.20%
NJ
Debt Securities, Available-for-sale [Line Items]
Weighted average geographic concentration of top four states	4.60%	4.70%

The weighted average maturity period of underlying mortgages, which is based on their current face amounts.

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- Definition

As of the balance sheet date, the weighted average of underlying mortgages at amortized cost to their fair values determined using defined pricing methodologies.

+ References

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- Definition

As of the balance sheet date, the weighted average credit score of underlying mortgages based on their FICO ratings.

+ References

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- Definition

As of the balance sheet date, the percentage of unpaid principal amount of underlying mortgages originated in a specified territory.

+ References

No definition available.

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- Definition

As of the balance sheet date, the weighted average of unpaid principal amounts of underlying mortgages.

+ References

No definition available.

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- Definition

As of the balance sheet date, the weighted average of underlying mortgages that are additionally secured in whole or in part with credit enhancements provided by third parties.

+ References

No definition available.

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- Definition

As of the balance sheet date, the weighted average of underlying mortgages that are owner occupied.

+ References

No definition available.

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- Definition

As of the balance sheet date, the weighted average of underlying mortgages that are single family residences.

+ References

No definition available.

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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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