Balance Sheet Offsetting - Disclosure Detail Of Balance Sheet Offsetting Of Financial Assets And Liabilities (Detail) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Derivative Liabilities
Net Amount	$ 86,290	$ 18,593
Customer-related positions
Derivative Assets
Gross Amounts Recognized	24,360	64,714
Gross Amounts Offset in the Consolidated Balance Sheet	0	0
Net Amounts Presented in the Consolidated Balance Sheet	24,360	64,714
Gross Amounts Not Offset in the Consolidated Balance Sheet, Financial Instruments	14	1,440
Gross Amounts Not Offset in the Consolidated Balance Sheet, Collateral Pledged (Received)	(16,650)	0
Net Amount	7,696	63,274
Derivative Liabilities
Gross Amounts Recognized	86,290	18,593
Gross Amounts Offset in the Consolidated Balance Sheet	0	0
Net Amounts Presented in the Consolidated Balance Sheet	86,290	18,593
Gross Amounts Not Offset in the Consolidated Balance Sheet, Financial Instruments	14	1,440
Gross Amounts Not Offset in the Consolidated Balance Sheet, Collateral Pledged (Received)	5,206	16,440
Net Amount	81,070	713
Interest rate swaps
Derivative Assets
Gross Amounts Recognized	5
Gross Amounts Offset in the Consolidated Balance Sheet	0
Net Amounts Presented in the Consolidated Balance Sheet	5
Gross Amounts Not Offset in the Consolidated Balance Sheet, Financial Instruments	0
Gross Amounts Not Offset in the Consolidated Balance Sheet, Collateral Pledged (Received)	0
Net Amount	5
Derivative Liabilities
Gross Amounts Recognized	3,206
Gross Amounts Offset in the Consolidated Balance Sheet	0
Net Amounts Presented in the Consolidated Balance Sheet	3,206
Gross Amounts Not Offset in the Consolidated Balance Sheet, Financial Instruments	0
Gross Amounts Not Offset in the Consolidated Balance Sheet, Collateral Pledged (Received)	3,206
Net Amount	0
Interest rate swaps \| Customer-related positions
Derivative Assets
Gross Amounts Recognized	23,818	64,338
Gross Amounts Offset in the Consolidated Balance Sheet	0	0
Net Amounts Presented in the Consolidated Balance Sheet	23,818	64,338
Gross Amounts Not Offset in the Consolidated Balance Sheet, Financial Instruments	14	1,440
Gross Amounts Not Offset in the Consolidated Balance Sheet, Collateral Pledged (Received)	(16,650)	0
Net Amount	7,154	62,898
Derivative Liabilities
Gross Amounts Recognized	82,404	17,880
Gross Amounts Offset in the Consolidated Balance Sheet	0	0
Net Amounts Presented in the Consolidated Balance Sheet	82,404	17,880
Gross Amounts Not Offset in the Consolidated Balance Sheet, Financial Instruments	14	1,440
Gross Amounts Not Offset in the Consolidated Balance Sheet, Collateral Pledged (Received)	2,000	16,440
Net Amount	80,390	0
Risk participation agreements \| Customer-related positions
Derivative Assets
Gross Amounts Recognized	55	315
Gross Amounts Offset in the Consolidated Balance Sheet	0	0
Net Amounts Presented in the Consolidated Balance Sheet	55	315
Gross Amounts Not Offset in the Consolidated Balance Sheet, Financial Instruments	0	0
Gross Amounts Not Offset in the Consolidated Balance Sheet, Collateral Pledged (Received)	0	0
Net Amount	55	315
Derivative Liabilities
Gross Amounts Recognized	134	580
Gross Amounts Offset in the Consolidated Balance Sheet	0	0
Net Amounts Presented in the Consolidated Balance Sheet	134	580
Gross Amounts Not Offset in the Consolidated Balance Sheet, Financial Instruments	0	0
Gross Amounts Not Offset in the Consolidated Balance Sheet, Collateral Pledged (Received)	0	0
Net Amount	134	580
Foreign currency exchange contracts - matched customer book \| Customer-related positions
Derivative Assets
Gross Amounts Recognized	428	61
Gross Amounts Offset in the Consolidated Balance Sheet	0	0
Net Amounts Presented in the Consolidated Balance Sheet	428	61
Gross Amounts Not Offset in the Consolidated Balance Sheet, Financial Instruments	0	0
Gross Amounts Not Offset in the Consolidated Balance Sheet, Collateral Pledged (Received)	0	0
Net Amount	428	61
Derivative Liabilities
Gross Amounts Recognized	414	46
Gross Amounts Offset in the Consolidated Balance Sheet	0	0
Net Amounts Presented in the Consolidated Balance Sheet	414	46
Gross Amounts Not Offset in the Consolidated Balance Sheet, Financial Instruments	0	0
Gross Amounts Not Offset in the Consolidated Balance Sheet, Collateral Pledged (Received)	0	0
Net Amount	414	46
Foreign currency exchange contracts - foreign currency loan \| Customer-related positions
Derivative Assets
Gross Amounts Recognized	54	0
Gross Amounts Offset in the Consolidated Balance Sheet	0	0
Net Amounts Presented in the Consolidated Balance Sheet	54	0
Gross Amounts Not Offset in the Consolidated Balance Sheet, Financial Instruments	0	0
Gross Amounts Not Offset in the Consolidated Balance Sheet, Collateral Pledged (Received)	0	0
Net Amount	54	0
Derivative Liabilities
Gross Amounts Recognized	132	87
Gross Amounts Offset in the Consolidated Balance Sheet	0	0
Net Amounts Presented in the Consolidated Balance Sheet	132	87
Gross Amounts Not Offset in the Consolidated Balance Sheet, Financial Instruments	0	0
Gross Amounts Not Offset in the Consolidated Balance Sheet, Collateral Pledged (Received)	0	0
Net Amount	$ 132	$ 87

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