Mortgage-Backed Securities - Geographical and Other Statistics (Detail) - Non-Agency RMBS - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Investment Holdings [Line Items]
Weighted average maturity (years)	23 years	23 years 7 months 6 days
Weighted average amortized loan to value	62.40%	63.20%
Weighted average FICO	717	719
Weighted average loan balance (in thousands)	$ 302	$ 313
Weighted average percentage owner occupied	81.10%	80.60%
Weighted average percentage single family residence	60.70%	60.00%
Weighted average current credit enhancement	0.90%	1.10%
CA
Investment Holdings [Line Items]
Weighted average geographic concentration of top four states	33.00%	32.50%
FL
Investment Holdings [Line Items]
Weighted average geographic concentration of top four states	7.20%	6.60%
NY
Investment Holdings [Line Items]
Weighted average geographic concentration of top four states	7.00%	6.30%
TX
Investment Holdings [Line Items]
Weighted average geographic concentration of top four states	2.20%	2.00%

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

No definition available.

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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

No definition available.

+ Details

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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

No definition available.

+ Details

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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.

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No definition available.

+ Details

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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.

+ Details

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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.

+ Details

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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.

+ Details

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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.

+ Details

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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.

+ References

No definition available.

+ Details

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