Allowance for Credit Losses - Schedule of Provisions for Credit Losses (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Provision (credit) for loan and lease losses:
Provision (credit) for loan and lease losses excluding unfunded commitments	$ 8,869	$ 9,374	$ 23,234	$ 27,070
Merger Day 1 CECL provision	69,487	0	69,487	0
Total provision (credit) for credit losses	87,528	4,660	100,514	17,607
Unfunded commitments
Provision (credit) for loan and lease losses:
Merger Day 1 unfunded commitments provision	8,415	0	8,415	0
Provision (credit) for unfunded commitments	725	(4,542)	(669)	(9,208)
Provision for other credit losses	9,140	(4,542)	7,746	(9,208)
Investment securities available-for-sale
Provision (credit) for loan and lease losses:
Provision for other credit losses	32	(172)	47	(255)
Commercial real estate
Provision (credit) for loan and lease losses:
Provision (credit) for loan and lease losses excluding unfunded commitments	5,040	(6,971)	7,507	(1,804)
Merger Day 1 CECL provision	31,820	0	31,820	0
Commercial
Provision (credit) for loan and lease losses:
Provision (credit) for loan and lease losses excluding unfunded commitments	6,637	16,632	18,224	29,511
Merger Day 1 CECL provision	17,891	0	17,891	0
Consumer
Provision (credit) for loan and lease losses:
Provision (credit) for loan and lease losses excluding unfunded commitments	(2,808)	(287)	(2,497)	(637)
Merger Day 1 CECL provision	$ 19,776	$ 0	$ 19,776	$ 0

Financing Receivable, Excluding Accrued Interest, Credit Loss Expense (Reversal), Excluding Merger Day One

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Amount, excluding accrued interest, of credit loss expense (reversal of expense) on financing receivable. Excludes net investment in lease.

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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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Amount of expense related to credit loss from transactions other than loan and lease transactions.

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