Derivatives - Credit Value Adjustment Recorded Related to Notional Amount of Derivatives Outstanding (Detail) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative, Fair Value, Net	$ (1)	$ (13)
Interest Rate Swap [Member] \| Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative, Notional Amount	942,491	945,046
Interest Rate Swap [Member] \| Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative, Fair Value, Net	(24,551)	(25,133)
Derivative, Notional Amount	570,000	570,000
Interest Rate Cap [Member] \| Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative, Notional Amount	37,547	37,647
interest Rate Collar [Member] \| Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative, Notional Amount	524	35,878
Credit Default Swap [Member] \| Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative, Notional Amount	180,388	206,325
Interest Rate Contract [Member] \| Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative, Notional Amount	67,674	38,155
Forward Contracts [Member] \| Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative, Fair Value, Net	(150)	(352)
Derivative, Notional Amount	71,000	39,000
Short [Member] \| Credit Default Swap, Selling Protection [Member] \| Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative, Notional Amount	$ 152,857	$ 121,265

Fair value of the assets less the liabilities of a derivative or group of derivatives.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482907/825-10-50-10

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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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480237/815-40-50-5

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- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480434/815-10-50-1B

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1A
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480434/815-10-50-1A

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