| **Derivatives - Credit Value Adjustment Recorded Related to Notional Amount of Derivatives Outstanding (Detail) - USD ($) $ in Thousands** | Mar. 31, 2022 | Dec. 31, 2021 |
|--------------------------------------------------------------------------------------------------------------------------------------------|---------------|---------------|
| Not Designated as Hedging Instrument [Member]                                                                                              |          |          |
| **Derivative [Line Items]**                                                                                                                |          |          |
| Derivative, Fair Value, Net                                                                                                                | $ (48)        | $ (395)       |
| Interest Rate Swap [Member] | Not Designated as Hedging Instrument [Member]                                                                |          |          |
| **Derivative [Line Items]**                                                                                                                |          |          |
| Derivative, Notional Amount                                                                                                                | 672,534       | 708,759       |
| Interest Rate Swap [Member] | Designated as Hedging Instrument [Member]                                                                    |          |          |
| **Derivative [Line Items]**                                                                                                                |          |          |
| Derivative, Fair Value, Net                                                                                                                | (24,948)      | (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                                                                                                                | 65,823        | 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                                                                                                                | 240,122       | 241,111       |
| Interest Rate Contract [Member] | Not Designated as Hedging Instrument [Member]                                                            |          |          |
| **Derivative [Line Items]**                                                                                                                |          |          |
| Derivative, Notional Amount                                                                                                                | 38,612        | 29,691        |
| Forward Contracts [Member] | Designated as Hedging Instrument [Member]                                                                     |          |          |
| **Derivative [Line Items]**                                                                                                                |          |          |
| Derivative, Fair Value, Net                                                                                                                | 837           | (29)          |
| Derivative, Notional Amount                                                                                                                | 41,000        | 38,000        |
| Foreign Exchange Contract [Member] | Designated as Hedging Instrument [Member]                                                             |          |          |
| **Derivative [Line Items]**                                                                                                                |          |          |
| Derivative, Fair Value, Net                                                                                                                | 11            | 12            |
| Derivative, Notional Amount                                                                                                                | 1,425         | 1,982         |
| Short [Member] | Credit Default Swap, Selling Protection [Member] | Not Designated as Hedging Instrument [Member]                          |          |          |
| **Derivative [Line Items]**                                                                                                                |          |          |
| Derivative, Notional Amount                                                                                                                | $ 77,114      | $ 95,618      |

| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - 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 http://asc.fasb.org/extlink&oid=123594938&loc=d3e13433-108611
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| X                                                                                                                                                                                                                                                                                                                                                                                                           |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - 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**Name:**us-gaap_DerivativeLineItems**Namespace Prefix:**us-gaap_**Data Type:**xbrli:stringItemType**Balance Type:**na**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - 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 http://asc.fasb.org/extlink&oid=125515794&loc=SL5580258-113959Reference 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 http://asc.fasb.org/extlink&oid=125515794&loc=SL5579245-113959
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