Loans and Allowances for Credit Losses, Activity in Allowance for Credit Losses (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Allowance for loan losses [Roll Forward]
Beginning balance	$ 277,123	$ 235,704	$ 256,421
Financing Receivable, Excluding Accrued Interest, Credit Loss Expense (Reversal)	15,791	59,518	428
Loans charged off	(18,835)	(27,316)	(28,746)
Recoveries of loans previously charged off	5,956	9,217	7,601
Ending balance	280,035	277,123	235,704
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Beginning Balance	48,977	60,919	32,977
Provision for off-balance sheet credit risk	2,663	(11,942)	27,942
Ending Balance	51,640	48,977	60,919
Provision Details [Abstract]
Total provision for credit losses	18,000	46,000	30,000
Recorded investment [Abstract]
Collectively measured for impairment, recorded investment	24,067,999	23,759,499
Individually measured for impairment, recorded investment	46,725	145,469
Total	24,114,724	23,904,968
Related allowance [Abstract]
Collectively measured for impairment, related allowance	279,759	274,431
Individually measured for impairment, related allowance	276	2,692
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest	280,035	277,123	235,704
Commercial [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	141,232	131,586	162,056
Financing Receivable, Excluding Accrued Interest, Credit Loss Expense (Reversal)	12,614	19,308	(12,782)
Loans charged off	(11,763)	(12,898)	(22,382)
Recoveries of loans previously charged off	3,070	3,236	4,694
Ending balance	145,153	141,232	131,586
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Beginning Balance	19,762	18,246	13,812
Provision for off-balance sheet credit risk	(1,716)	1,516	4,434
Ending Balance	18,046	19,762	18,246
Recorded investment [Abstract]
Collectively measured for impairment, recorded investment	15,015,489	14,693,638
Individually measured for impairment, recorded investment	14,647	110,131
Total	15,030,136	14,803,769
Related allowance [Abstract]
Collectively measured for impairment, related allowance	144,877	138,540
Individually measured for impairment, related allowance	276	2,692
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest	145,153	141,232	131,586
Commercial real estate [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	94,718	57,648	58,553
Financing Receivable, Excluding Accrued Interest, Credit Loss Expense (Reversal)	(2,481)	42,151	(813)
Loans charged off	(1,455)	(8,446)	(269)
Recoveries of loans previously charged off	290	3,365	177
Ending balance	91,072	94,718	57,648
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Beginning Balance	27,439	40,490	17,442
Provision for off-balance sheet credit risk	4,520	(13,051)	23,048
Ending Balance	31,959	27,439	40,490
Recorded investment [Abstract]
Collectively measured for impairment, recorded investment	5,048,547	5,330,327
Individually measured for impairment, recorded investment	9,905	7,320
Total	5,058,452	5,337,647
Related allowance [Abstract]
Collectively measured for impairment, related allowance	91,072	94,718
Individually measured for impairment, related allowance	0	0
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest	91,072	94,718	57,648
Loans to individuals [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	41,173	46,470	35,812
Financing Receivable, Excluding Accrued Interest, Credit Loss Expense (Reversal)	5,658	(1,941)	14,023
Loans charged off	(5,617)	(5,972)	(6,095)
Recoveries of loans previously charged off	2,596	2,616	2,730
Ending balance	43,810	41,173	46,470
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Beginning Balance	1,776	2,183	1,723
Provision for off-balance sheet credit risk	(141)	(407)	460
Ending Balance	1,635	1,776	2,183
Recorded investment [Abstract]
Collectively measured for impairment, recorded investment	4,003,963	3,735,534
Individually measured for impairment, recorded investment	22,173	28,018
Total	4,026,136	3,763,552
Related allowance [Abstract]
Collectively measured for impairment, related allowance	43,810	41,173
Individually measured for impairment, related allowance	0	0
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest	$ 43,810	$ 41,173	$ 46,470

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Amount of expected credit loss for credit exposure on off-balance-sheet commitment, including but not limited to, loan commitment, standby letter of credit, financial guarantee not accounted for as insurance. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging.

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