Derivatives - Credit Value Adjustment Recorded Related to Notional Amount of Derivatives Outstanding (Detail) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Credit value adjustment	$ (27)	$ (395)
Not Designated as Hedging Instrument [Member] \| Interest Rate Swap [Member]
Derivative [Line Items]
Derivative, Notional Amount	816,745	708,759
Not Designated as Hedging Instrument [Member] \| Interest Rate Cap [Member]
Derivative [Line Items]
Derivative, Notional Amount	15,340	66,007
Not Designated as Hedging Instrument [Member] \| Interest Rate Collar [Member]
Derivative [Line Items]
Derivative, Notional Amount	35,354	35,354
Not Designated as Hedging Instrument [Member] \| Credit Default Swap, Buying Protection [Member]
Derivative [Line Items]
Derivative, Notional Amount	256,043	241,111
Not Designated as Hedging Instrument [Member] \| Credit Default Swap, Selling Protection [Member]
Derivative [Line Items]
Derivative, Sold Protection Notional Amount	(100,741)	(95,618)
Not Designated as Hedging Instrument [Member] \| Interest Rate Contract [Member]
Derivative [Line Items]
Derivative, Notional Amount	12,009	29,691
Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative, Fair Value, Net	(38,596)	(7,022)
Designated as Hedging Instrument [Member] \| Interest Rate Swap [Member]
Derivative [Line Items]
Derivative, Notional Amount	570,000	570,000
Designated as Hedging Instrument [Member] \| Forward Contracts [Member]
Derivative [Line Items]
Derivative, Notional Amount	16,000	38,000
Derivative, Fair Value, Net	63	(29)
Designated as Hedging Instrument [Member] \| Foreign Exchange Contract [Member]
Derivative [Line Items]
Derivative, Notional Amount	0	1,982
Derivative, Fair Value, Net	$ 0	$ 12

Derivative, Sold Protection Notional Amount

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of credit risk valuation adjustment to derivative liabilities to properly reflect the credit quality of the entity.

+ References

No definition available.

+ Details

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- Definition

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

+ References

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

+ Details

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Balance Type:	debit
Period Type:	instant

- 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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Period Type:	duration

- 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

+ Details

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