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Loans and Allowance for Credit Losses - Schedule of Composition of Loans and Impact of Adoption (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	$ 48,764,162	$ 36,285,887
Allowance for credit losses on loans	(569,520)	(392,522)	$ (307,610)	$ (303,671)
Net loans	48,194,642	35,893,365
Taxable	2,621,105	2,139,437	1,815,390
Portfolio Segment Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	0	0
Net loans	0	0
Portfolio Segment After Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	48,764,162	36,285,887
Allowance for credit losses on loans	(569,520)	(392,522)
Net loans	48,194,642	35,893,365
Taxable	540,100	163,300
Commercial
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	14,983,861	10,288,560
Allowance for credit losses on loans	(244,670)	(148,722)	(118,333)	(120,612)
Commercial \| Portfolio Segment Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	(220,410)	(232,301)
Commercial \| Portfolio Segment After Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	14,763,451	10,056,259
Commercial real estate
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	22,050,007	16,307,486
Allowance for credit losses on loans	(268,332)	(200,309)	(155,099)	(138,244)
Commercial real estate \| Portfolio Segment Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	(175,670)	(174,438)
Commercial real estate \| Portfolio Segment After Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	21,874,337	16,133,048
BBCC
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for credit losses on loans	(2,371)	(2,813)	(2,887)	(2,431)
BBCC \| Portfolio Segment Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	396,080	406,739
BBCC \| Portfolio Segment After Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	396,080	406,739
Residential real estate
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	8,467,496	6,797,586
Allowance for credit losses on loans	(34,394)	(22,922)	(20,837)	(21,916)
Residential real estate \| Portfolio Segment Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	0	0
Residential real estate \| Portfolio Segment After Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	8,467,496	6,797,586
Consumer
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	3,262,798	2,892,255
Consumer \| Portfolio Segment Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	(3,262,798)	(2,892,255)
Indirect
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	1,075,235	1,096,778
Allowance for credit losses on loans	(8,021)	(8,434)	(1,236)	(1,532)
Indirect \| Portfolio Segment Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	1,075,235	1,096,778
Indirect \| Portfolio Segment After Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	1,075,235	1,096,778
Direct
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	649,297	514,144
Allowance for credit losses on loans	(2,478)	(2,304)	(3,169)	(12,116)
Direct \| Portfolio Segment Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	649,297	514,144
Direct \| Portfolio Segment After Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	649,297	514,144
Home equity
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	1,538,266	1,281,333
Allowance for credit losses on loans	(9,254)	(7,018)	$ (6,049)	$ (6,820)
Home equity \| Portfolio Segment Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	1,538,266	1,281,333
Home equity \| Portfolio Segment After Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	1,538,266	1,281,333
Direct Finance Leases
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	$ 75,100	$ 120,600