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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, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	$ 36,285,887	$ 32,991,927
Allowance for credit losses on loans	(392,522)	(307,610)	$ (303,671)	$ (107,341)
Net loans	35,893,365	32,684,317
Taxable	2,139,437	1,815,390	1,177,816
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	36,285,887	32,991,927
Allowance for credit losses on loans	(392,522)	(307,610)
Net loans	35,893,365	32,684,317
Taxable	163,300	93,700
Commercial
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	10,288,560	9,512,230
Allowance for credit losses on loans	(148,722)	(118,333)	(120,612)	(27,232)
Commercial \| Portfolio Segment Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	(232,301)	(232,764)
Commercial \| Portfolio Segment After Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	10,056,259	9,279,466
Commercial real estate
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	16,307,486	14,140,629
Allowance for credit losses on loans	(200,309)	(155,099)	(138,244)	(64,004)
Commercial real estate \| Portfolio Segment Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	(174,438)	(169,058)
Commercial real estate \| Portfolio Segment After Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	16,133,048	13,971,571
BBCC
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for credit losses on loans	(2,813)	(2,887)	(2,431)	(2,458)
BBCC \| Portfolio Segment Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	406,739	401,822
BBCC \| Portfolio Segment After Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	406,739	401,822
Residential real estate
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	6,797,586	6,699,443
Allowance for credit losses on loans	(22,922)	(20,837)	(21,916)	(9,347)
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	6,797,586	6,699,443
Consumer
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	2,892,255	2,639,625
Consumer \| Portfolio Segment Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	(2,892,255)	(2,639,625)
Indirect
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	1,096,778	1,050,982
Allowance for credit losses on loans	(8,434)	(1,236)	(1,532)	(1,743)
Indirect \| Portfolio Segment Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	1,096,778	1,050,982
Indirect \| Portfolio Segment After Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	1,096,778	1,050,982
Direct
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	514,144	523,172
Allowance for credit losses on loans	(2,304)	(3,169)	(12,116)	(528)
Direct \| Portfolio Segment Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	514,144	523,172
Direct \| Portfolio Segment After Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	514,144	523,172
Home equity
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	1,281,333	1,065,471
Allowance for credit losses on loans	(7,018)	(6,049)	$ (6,820)	$ (2,029)
Home equity \| Portfolio Segment Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	1,281,333	1,065,471
Home equity \| Portfolio Segment After Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	1,281,333	1,065,471
Direct Finance Leases
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	$ 120,600	$ 169,700