Derivatives - Credit Value Adjustment Recorded Related to Notional Amount of Derivatives Outstanding (Detail) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative, Fair Value, Net	$ 0	$ (395)
Interest Rate Swap [Member] \| Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative, Notional Amount	823,176	708,759
Interest Rate Swap [Member] \| Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative, Fair Value, Net	(40,776)	(7,022)
Derivative, Notional Amount	570,000	570,000
Interest Rate Cap [Member] \| Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative, Notional Amount	15,421	66,007
interest Rate Collar [Member] \| Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative, Notional Amount	35,354	35,354
Credit Default Swap [Member] \| Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative, Notional Amount	264,306	241,111
Interest Rate Contract [Member] \| Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative, Notional Amount	21,991	29,691
Forward Contracts [Member] \| Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative, Fair Value, Net	1,007	(29)
Derivative, Notional Amount	23,000	38,000
Foreign Exchange Contract [Member] \| Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative, Fair Value, Net	0	12
Derivative, Notional Amount	0	1,982
Short [Member] \| Credit Default Swap, Selling Protection [Member] \| Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative, Notional Amount	$ 122,041	$ 95,618

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI https://asc.fasb.org/extlink&oid=123594938&loc=d3e13433-108611

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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.

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI https://asc.fasb.org/extlink&oid=125515794&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI https://asc.fasb.org/extlink&oid=125515794&loc=SL5579245-113959

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