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Balance Sheet Offsetting - Financial Instruments Derivative Assets Liabilities and Resell Agreements Net of Amount Not Offset (Detail) - USD ($) $ in Thousands | Jun. 30, 2025 | Dec. 31, 2024
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Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items] |  |
Net Amount Recognized, Derivatives, Financial Assets | $ 97,265 | $ 101,329
Gross Amounts Not Offset, Financial Instruments, Total Derivatives, Financial Assets | (33,972) | (25,714)
Gross Amount Not Offset Collateral, Derivatives, Financial Assets | (58,194) | (74,157)
Net Amount, Derivatives, Financial Assets | 5,099 | 1,458
Net Amount Recognized, Resell agreements, Financial Assets | 9,650 | 9,650
Gross Amounts Not Offset Financial Instruments, Resell Agreements | 0 | 0
Gross Amounts Not Offset Collateral, Resell Agreements, Financial Assets | (9,650) | (9,650)
Net Amount, Financial Assets, Resell Agreements | 0 | 0
Net Amount Recognized, Total Financial Assets | 106,915 | 110,979
Gross Amounts Not Offset Collateral, Financial Assets | (67,844) | (83,807)
Net Amount, Financial Assets | 5,099 | 1,458
Net Amount Recognized, Derivatives, Financial Liabilities | 45,918 | 26,019
Gross Amounts Not Offset Financial Instruments, Total Derivatives, Financial Liabilities | (33,972) | (25,714)
Gross Amounts Not Offset Collateral, Derivatives, Financial Liabilities | (11,386) | (305)
Net Amount, Derivatives, Financial Liabilities | 560 | 0
Net Amount Recognized, Repurchase Agreements, Financial Liabilities | 4,418,379 | 4,342,941
Gross Amounts Not Offset Financial Instruments, Repurchase Agreements, Financial Liabilities | 0 | 0
Gross Amounts Not Offset Collateral, Repurchase Agreements, Financial Liabilities | (4,418,379) | (4,342,941)
Net Amount, Repurchase Agreements, Financial Liabilities | 0 | 0
Net Amount Recognized, Total Financial Liabilities | 4,464,297 | 4,368,960
Gross Amounts Not Offset Collateral, Financial Liabilities | (4,429,765) | (4,343,246)
Net Amount, Financial Liabilities | 560 | 0
Counterparty H |  |
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items] |  |
Net Amount Recognized, Derivatives, Financial Assets | 38,116 | 36,286
Gross Amounts Not Offset, Financial Instruments, Total Derivatives, Financial Assets | (9,006) | (10,129)
Gross Amount Not Offset Collateral, Derivatives, Financial Assets | (27,830) | (26,157)
Net Amount, Derivatives, Financial Assets | 1,280 | 0
Net Amount Recognized, Derivatives, Financial Liabilities | 9,006 | 10,129
Gross Amounts Not Offset Financial Instruments, Total Derivatives, Financial Liabilities | (9,006) | (10,129)
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 | 25,215 | 15,505
Gross Amounts Not Offset, Financial Instruments, Total Derivatives, Financial Assets | (11,392) | (2,322)
Gross Amount Not Offset Collateral, Derivatives, Financial Assets | (11,122) | (11,759)
Net Amount, Derivatives, Financial Assets | 2,701 | 1,424
Net Amount Recognized, Derivatives, Financial Liabilities | 11,392 | 2,322
Gross Amounts Not Offset Financial Instruments, Total Derivatives, Financial Liabilities | (11,392) | (2,322)
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 | 18,457 | 22,338
Gross Amounts Not Offset, Financial Instruments, Total Derivatives, Financial Assets | (3,686) | (4,522)
Gross Amount Not Offset Collateral, Derivatives, Financial Assets | (13,887) | (17,816)
Net Amount, Derivatives, Financial Assets | 884 | 0
Net Amount Recognized, Derivatives, Financial Liabilities | 3,686 | 4,522
Gross Amounts Not Offset Financial Instruments, Total Derivatives, Financial Liabilities | (3,686) | (4,522)
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 | 8,525 | 14,219
Gross Amounts Not Offset, Financial Instruments, Total Derivatives, Financial Assets | (6,206) | (2,109)
Gross Amount Not Offset Collateral, Derivatives, Financial Assets | (2,319) | (12,100)
Net Amount, Derivatives, Financial Assets | 0 | 10
Net Amount Recognized, Derivatives, Financial Liabilities | 6,206 | 2,109
Gross Amounts Not Offset Financial Instruments, Total Derivatives, Financial Liabilities | (6,206) | (2,109)
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 | 6,952 | 12,981
Gross Amounts Not Offset, Financial Instruments, Total Derivatives, Financial Assets | (3,682) | (6,632)
Gross Amount Not Offset Collateral, Derivatives, Financial Assets | (3,036) | (6,325)
Net Amount, Derivatives, Financial Assets | 234 | 24
Net Amount Recognized, Derivatives, Financial Liabilities | 15,628 | 6,937
Gross Amounts Not Offset Financial Instruments, Total Derivatives, Financial Liabilities | (3,682) | (6,632)
Gross Amounts Not Offset Collateral, Derivatives, Financial Liabilities | (11,386) | (305)
Net Amount, Derivatives, Financial Liabilities | $ 560 | $ 0

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