Loans and Allowance for Loan Losses - Schedule of Rollforward of Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024
Allowance for loan losses:
Beginning balance	$ 464,831	$ 485,101	$ 486,845	$ 479,385	$ 479,385
Charge-offs	(19,969)	(34,106)	(81,530)	(126,965)	(160,948)
Recoveries	4,742	7,054	26,637	21,072
Provision for (reversal of) loan losses	19,917	26,936	37,569	111,493
Ending balance	469,521	484,985	469,521	484,985	486,845
Commercial & Industrial
Allowance for loan losses:
Beginning balance	205,240	220,730	210,525	218,970	218,970
Charge-offs	(11,648)	(21,484)	(38,228)	(93,806)
Recoveries	1,962	5,094	17,674	12,971
Provision for (reversal of) loan losses	13,468	(4,272)	19,051	61,933
Ending balance	209,022	200,068	209,022	200,068	210,525
Commercial Real Estate
Allowance for loan losses:
Beginning balance	117,739	141,680	134,021	133,758	133,758
Charge-offs	(384)	(5,833)	(19,211)	(9,807)
Recoveries	53	333	1,172	1,562
Provision for (reversal of) loan losses	5,989	7,408	7,415	18,075
Ending balance	123,397	143,588	123,397	143,588	134,021
Consumer
Allowance for loan losses:
Beginning balance	141,852	122,691	142,299	126,657	126,657
Charge-offs	(7,937)	(6,789)	(24,091)	(23,352)
Recoveries	2,727	1,627	7,791	6,539
Provision for (reversal of) loan losses	460	23,800	11,103	31,485
Ending balance	$ 137,102	$ 141,329	$ 137,102	$ 141,329	$ 142,299

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

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Amount, excluding accrued interest, of increase in allowance for credit loss on financing receivable from recovery. Excludes net investment in lease.

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Amount, excluding accrued interest, of decrease in allowance for credit loss on financing receivable from writeoff. Excludes net investment in lease.

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- Definition

Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

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