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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, 2023 | Dec. 31, 2022
--- | --- | ---
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items] |  |
Net Amount Recognized, Derivatives, Financial Assets | $ 130,330 | $ 118,994
Gross Amounts Not Offset, Financial Instruments, Total Derivatives, Financial Assets | (29,402) | (62,528)
Gross Amount Not Offset Collateral, Derivatives, Financial Assets | (100,589) | (55,968)
Net Amount, Derivatives, Financial Assets | 339 | 498
Net Amount Recognized, Resell agreements, Financial Assets | 84,650 | 87,150
Gross Amounts Not Offset Financial Instruments, Resell Agreements | 0 | 0
Gross Amounts Not Offset Collateral, Resell Agreements, Financial Assets | (84,650) | (87,150)
Net Amount, Financial Assets, Resell Agreements | 0 | 0
Net Amount Recognized, Total Financial Assets | 214,980 | 206,144
Gross Amounts Not Offset Collateral, Financial Assets | (185,239) | (143,118)
Net Amount, Financial Assets | 339 | 498
Net Amount Recognized, Derivatives, Financial Liabilities | 29,402 | 73,829
Gross Amounts Not Offset Financial Instruments, Total Derivatives, Financial Liabilities | (29,402) | (62,528)
Gross Amounts Not Offset Collateral, Derivatives, Financial Liabilities | 0 | (9,330)
Net Amount, Derivatives, Financial Liabilities | 0 | 1,971
Net Amount Recognized, Repurchase Agreements, Financial Liabilities | 3,569,870 | 4,660,641
Gross Amounts Not Offset Financial Instruments, Repurchase Agreements, Financial Liabilities | 0 | 0
Gross Amounts Not Offset Collateral, Repurchase Agreements, Financial Liabilities | (3,569,870) | (4,660,641)
Net Amount, Repurchase Agreements, Financial Liabilities | 0 | 0
Net Amount Recognized, Total Financial Liabilities | 3,599,272 | 4,734,470
Gross Amounts Not Offset Collateral, Financial Liabilities | (3,569,870) | (4,669,971)
Net Amount, Financial Liabilities | 0 | 1,971
Counterparty B |  |
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items] |  |
Net Amount Recognized, Derivatives, Financial Assets | 32,143 | 39,370
Gross Amounts Not Offset, Financial Instruments, Total Derivatives, Financial Assets | (9,548) | (24,500)
Gross Amount Not Offset Collateral, Derivatives, Financial Assets | (22,595) | (14,870)
Net Amount, Derivatives, Financial Assets | 0 | 0
Net Amount Recognized, Derivatives, Financial Liabilities | 9,548 | 24,500
Gross Amounts Not Offset Financial Instruments, Total Derivatives, Financial Liabilities | (9,548) | (24,500)
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 | 16,312 | 14,430
Gross Amounts Not Offset, Financial Instruments, Total Derivatives, Financial Assets | (896) | (47)
Gross Amount Not Offset Collateral, Derivatives, Financial Assets | (15,240) | (14,131)
Net Amount, Derivatives, Financial Assets | 176 | 252
Net Amount Recognized, Derivatives, Financial Liabilities | 896 | 47
Gross Amounts Not Offset Financial Instruments, Total Derivatives, Financial Liabilities | (896) | (47)
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 | 18,387 | 17,297
Gross Amounts Not Offset, Financial Instruments, Total Derivatives, Financial Assets | (8,839) | (17,297)
Gross Amount Not Offset Collateral, Derivatives, Financial Assets | (9,463) | 0
Net Amount, Derivatives, Financial Assets | 85 | 0
Net Amount Recognized, Derivatives, Financial Liabilities | 8,839 | 27,747
Gross Amounts Not Offset Financial Instruments, Total Derivatives, Financial Liabilities | (8,839) | (17,297)
Gross Amounts Not Offset Collateral, Derivatives, Financial Liabilities | 0 | (8,479)
Net Amount, Derivatives, Financial Liabilities | 0 | 1,971
Counterparty G |  |
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items] |  |
Net Amount Recognized, Derivatives, Financial Assets | 10,484 | 10,660
Gross Amounts Not Offset, Financial Instruments, Total Derivatives, Financial Assets | 0 | 0
Gross Amount Not Offset Collateral, Derivatives, Financial Assets | (10,430) | (10,660)
Net Amount, Derivatives, Financial Assets | 54 | 0
Net Amount Recognized, Derivatives, Financial Liabilities |  | 0
Gross Amounts Not Offset Financial Instruments, Total Derivatives, Financial Liabilities |  | 0
Gross Amounts Not Offset Collateral, Derivatives, Financial Liabilities |  | 0
Net Amount, Derivatives, Financial Liabilities |  | 0
Other counterparties |  |
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items] |  |
Net Amount Recognized, Derivatives, Financial Assets | 53,004 | 37,237
Gross Amounts Not Offset, Financial Instruments, Total Derivatives, Financial Assets | (10,119) | (20,684)
Gross Amount Not Offset Collateral, Derivatives, Financial Assets | (42,861) | (16,307)
Net Amount, Derivatives, Financial Assets | 24 | 246
Net Amount Recognized, Derivatives, Financial Liabilities | 10,119 | 21,535
Gross Amounts Not Offset Financial Instruments, Total Derivatives, Financial Liabilities | (10,119) | (20,684)
Gross Amounts Not Offset Collateral, Derivatives, Financial Liabilities | 0 | (851)
Net Amount, Derivatives, Financial Liabilities | $ 0 | $ 0

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