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Balance Sheet Offsetting - Financial Instruments Derivative Assets Liabilities and Resell Agreements Net of Amount Not Offset (Detail) - USD ($) $ in Thousands | Mar. 31, 2024 | Dec. 31, 2023
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Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items] |  |
Net Amount Recognized, Derivatives, Financial Assets | $ 102,891 | $ 119,723
Gross Amounts Not Offset, Financial Instruments, Total Derivatives, Financial Assets | (40,475) | (32,431)
Gross Amount Not Offset Collateral, Derivatives, Financial Assets | (61,500) | (84,839)
Net Amount, Derivatives, Financial Assets | 916 | 2,453
Net Amount Recognized, Resell agreements, Financial Assets | 84,650 | 84,650
Gross Amounts Not Offset Financial Instruments, Resell Agreements | 0 | 0
Gross Amounts Not Offset Collateral, Resell Agreements, Financial Assets | (84,650) | (84,650)
Net Amount, Financial Assets, Resell Agreements | 0 | 0
Net Amount Recognized, Total Financial Assets | 187,541 | 204,373
Gross Amounts Not Offset Collateral, Financial Assets | (146,150) | (169,489)
Net Amount, Financial Assets | 916 | 2,453
Net Amount Recognized, Derivatives, Financial Liabilities | 40,810 | 41,311
Gross Amounts Not Offset Financial Instruments, Total Derivatives, Financial Liabilities | (40,475) | (32,431)
Gross Amounts Not Offset Collateral, Derivatives, Financial Liabilities | (335) | (8,580)
Net Amount, Derivatives, Financial Liabilities | 0 | 300
Net Amount Recognized, Repurchase Agreements, Financial Liabilities | 3,943,207 | 4,127,188
Gross Amounts Not Offset Financial Instruments, Repurchase Agreements, Financial Liabilities | 0 | 0
Gross Amounts Not Offset Collateral, Repurchase Agreements, Financial Liabilities | (3,943,207) | (4,127,188)
Net Amount, Repurchase Agreements, Financial Liabilities | 0 | 0
Net Amount Recognized, Total Financial Liabilities | 3,984,017 | 4,168,499
Gross Amounts Not Offset Collateral, Financial Liabilities | (3,943,542) | (4,135,768)
Net Amount, Financial Liabilities | 0 | 300
Counterparty H |  |
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items] |  |
Net Amount Recognized, Derivatives, Financial Assets | 31,738 | 36,551
Gross Amounts Not Offset, Financial Instruments, Total Derivatives, Financial Assets | (12,183) | (8,870)
Gross Amount Not Offset Collateral, Derivatives, Financial Assets | (19,555) | (27,170)
Net Amount, Derivatives, Financial Assets | 0 | 511
Net Amount Recognized, Derivatives, Financial Liabilities | 12,183 | 8,870
Gross Amounts Not Offset Financial Instruments, Total Derivatives, Financial Liabilities | (12,183) | (8,870)
Gross Amounts Not Offset Collateral, Derivatives, Financial Liabilities | 0 | 0
Net Amount, Derivatives, Financial Liabilities | 0 | 0
Counterparty F |  |
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items] |  |
Net Amount Recognized, Derivatives, Financial Assets | 17,484 | 31,202
Gross Amounts Not Offset, Financial Instruments, Total Derivatives, Financial Assets | (15,966) | (7,444)
Gross Amount Not Offset Collateral, Derivatives, Financial Assets | (1,136) | (22,954)
Net Amount, Derivatives, Financial Assets | 382 | 804
Net Amount Recognized, Derivatives, Financial Liabilities | 15,966 | 7,444
Gross Amounts Not Offset Financial Instruments, Total Derivatives, Financial Liabilities | (15,966) | (7,444)
Gross Amounts Not Offset Collateral, Derivatives, Financial Liabilities | 0 | 0
Net Amount, Derivatives, Financial Liabilities | 0 | 0
Counterparty B |  |
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items] |  |
Net Amount Recognized, Derivatives, Financial Assets | 22,234 | 23,829
Gross Amounts Not Offset, Financial Instruments, Total Derivatives, Financial Assets | (2,775) | (5,151)
Gross Amount Not Offset Collateral, Derivatives, Financial Assets | (19,459) | (18,472)
Net Amount, Derivatives, Financial Assets | 0 | 206
Net Amount Recognized, Derivatives, Financial Liabilities | 2,775 | 5,151
Gross Amounts Not Offset Financial Instruments, Total Derivatives, Financial Liabilities | (2,775) | (5,151)
Gross Amounts Not Offset Collateral, Derivatives, Financial Liabilities | 0 | 0
Net Amount, Derivatives, Financial Liabilities | 0 | 0
Counterparty E |  |
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items] |  |
Net Amount Recognized, Derivatives, Financial Assets | 15,519 | 13,271
Gross Amounts Not Offset, Financial Instruments, Total Derivatives, Financial Assets | (2,228) | (4,548)
Gross Amount Not Offset Collateral, Derivatives, Financial Assets | (13,080) | (8,723)
Net Amount, Derivatives, Financial Assets | 211 | 0
Net Amount Recognized, Derivatives, Financial Liabilities | 2,228 | 4,548
Gross Amounts Not Offset Financial Instruments, Total Derivatives, Financial Liabilities | (2,228) | (4,548)
Gross Amounts Not Offset Collateral, Derivatives, Financial Liabilities | 0 | 0
Net Amount, Derivatives, Financial Liabilities | 0 | 0
Other counterparties |  |
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items] |  |
Net Amount Recognized, Derivatives, Financial Assets | 15,916 | 14,870
Gross Amounts Not Offset, Financial Instruments, Total Derivatives, Financial Assets | (7,323) | (6,418)
Gross Amount Not Offset Collateral, Derivatives, Financial Assets | (8,270) | (7,520)
Net Amount, Derivatives, Financial Assets | 323 | 932
Net Amount Recognized, Derivatives, Financial Liabilities | 7,658 | 15,298
Gross Amounts Not Offset Financial Instruments, Total Derivatives, Financial Liabilities | (7,323) | (6,418)
Gross Amounts Not Offset Collateral, Derivatives, Financial Liabilities | (335) | (8,580)
Net Amount, Derivatives, Financial Liabilities | $ 0 | $ 300

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Namespace Prefix: |
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Period Type: |

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Namespace Prefix: |
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Balance Type: |
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Namespace Prefix: |
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