Mortgage-Backed Securities - Geographical and Other Statistics (Detail) - Non-agency MBS - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Investment Holdings [Line Items]
Weighted average maturity (years)	22 years 10 months 24 days	21 years 3 months 18 days
Weighted average amortized loan to value	63.50%	62.90%
Weighted average FICO	714	708
Weighted average loan balance (in thousands)	$ 294	$ 308
Weighted average percentage owner occupied	86.50%	85.70%
Weighted average percentage single family residence	60.70%	63.80%
Weighted average current credit enhancement	1.20%	1.40%
CA
Investment Holdings [Line Items]
Weighted average geographic concentration of top four states	32.90%	33.80%
FL
Investment Holdings [Line Items]
Weighted average geographic concentration of top four states	7.10%	7.70%
NY
Investment Holdings [Line Items]
Weighted average geographic concentration of top four states	6.60%	7.40%
TX
Investment Holdings [Line Items]
Weighted average geographic concentration of top four states	2.20%
NJ
Investment Holdings [Line Items]
Weighted average geographic concentration of top four states		2.10%

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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