Balance Sheet Offsetting - Disclosure Detail Of Balance Sheet Offsetting Of Financial Assets And Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Customer-related positions
Derivative Assets
Gross Amounts Recognized	$ 64,714	$ 142,643
Gross Amounts Offset in the Statement of Financial Position	0	0
Net Amounts Presented in the Statement of Financial Position	64,714	142,643
Gross Amounts Not Offset in the Statement of Financial Position, Financial Instruments	1,440	48
Gross Amounts Not Offset in the Statement of Financial Position, Collateral Pledged (Received)	0	(1)
Net Amount	63,274	142,594
Derivative Liabilities
Gross Amounts Recognized	18,593	43,976
Gross Amounts Offset in the Statement of Financial Position	0	0
Net Amounts Presented in the Statement of Financial Position	18,593	43,976
Gross Amounts Not Offset in the Statement of Financial Position, Financial Instruments	1,440	48
Gross Amounts Not Offset in the Statement of Financial Position, Collateral Pledged (Received)	16,440	42,552
Net Amount	713	1,376
Interest rate swaps \| Customer-related positions
Derivative Assets
Gross Amounts Recognized	64,338	141,822
Gross Amounts Offset in the Statement of Financial Position	0	0
Net Amounts Presented in the Statement of Financial Position	64,338	141,822
Gross Amounts Not Offset in the Statement of Financial Position, Financial Instruments	1,440	48
Gross Amounts Not Offset in the Statement of Financial Position, Collateral Pledged (Received)	0	0
Net Amount	62,898	141,774
Derivative Liabilities
Gross Amounts Recognized	17,880	42,600
Gross Amounts Offset in the Statement of Financial Position	0	0
Net Amounts Presented in the Statement of Financial Position	17,880	42,600
Gross Amounts Not Offset in the Statement of Financial Position, Financial Instruments	1,440	48
Gross Amounts Not Offset in the Statement of Financial Position, Collateral Pledged (Received)	16,440	42,552
Net Amount	0	0
Risk participation agreements \| Customer-related positions
Derivative Assets
Gross Amounts Recognized	315	722
Gross Amounts Offset in the Statement of Financial Position	0	0
Net Amounts Presented in the Statement of Financial Position	315	722
Gross Amounts Not Offset in the Statement of Financial Position, Financial Instruments	0	0
Gross Amounts Not Offset in the Statement of Financial Position, Collateral Pledged (Received)	0	0
Net Amount	315	722
Derivative Liabilities
Gross Amounts Recognized	580	1,230
Gross Amounts Offset in the Statement of Financial Position	0	0
Net Amounts Presented in the Statement of Financial Position	580	1,230
Gross Amounts Not Offset in the Statement of Financial Position, Financial Instruments	0	0
Gross Amounts Not Offset in the Statement of Financial Position, Collateral Pledged (Received)	0	0
Net Amount	580	1,230
Foreign currency exchange contracts — matched customer book \| Customer-related positions
Derivative Assets
Gross Amounts Recognized	61	90
Gross Amounts Offset in the Statement of Financial Position	0	0
Net Amounts Presented in the Statement of Financial Position	61	90
Gross Amounts Not Offset in the Statement of Financial Position, Financial Instruments	0	0
Gross Amounts Not Offset in the Statement of Financial Position, Collateral Pledged (Received)	0	(1)
Net Amount	61	89
Derivative Liabilities
Gross Amounts Recognized	46	77
Gross Amounts Offset in the Statement of Financial Position	0	0
Net Amounts Presented in the Statement of Financial Position	46	77
Gross Amounts Not Offset in the Statement of Financial Position, Financial Instruments	0	0
Gross Amounts Not Offset in the Statement of Financial Position, Collateral Pledged (Received)	0	0
Net Amount	46	77
Foreign currency exchange contracts — foreign currency loan
Derivative Assets
Gross Amounts Recognized	0	9
Gross Amounts Offset in the Statement of Financial Position	0	0
Net Amounts Presented in the Statement of Financial Position	0	9
Gross Amounts Not Offset in the Statement of Financial Position, Financial Instruments	0	0
Gross Amounts Not Offset in the Statement of Financial Position, Collateral Pledged (Received)	0	0
Net Amount	0	9
Foreign currency exchange contracts — foreign currency loan \| Customer-related positions
Derivative Liabilities
Gross Amounts Recognized	87	69
Gross Amounts Offset in the Statement of Financial Position	0	0
Net Amounts Presented in the Statement of Financial Position	87	69
Gross Amounts Not Offset in the Statement of Financial Position, Financial Instruments	0	0
Gross Amounts Not Offset in the Statement of Financial Position, Collateral Pledged (Received)	0	0
Net Amount	$ 87	$ 69

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