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Loans and Allowance for Credit Losses - Schedule of Composition of Loans and Impact of Adoption (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2022
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	$ 36,150,513		$ 36,150,513		$ 32,991,927
Allowance for credit losses on loans	(366,335)	$ (300,555)	(366,335)	$ (300,555)	(307,610)	$ (319,713)	$ (298,711)	$ (303,671)
Net loans	35,784,178		35,784,178		32,684,317
Taxable	545,622	449,896	1,032,983	860,271
Portfolio Segment Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	0		0		0
Net loans	0		0		0
Portfolio Segment After Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	36,150,513		36,150,513		32,991,927
Allowance for credit losses on loans	(366,335)		(366,335)		(307,610)
Net loans	35,784,178		35,784,178		32,684,317
Taxable			199,700		93,700
Commercial
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	10,332,631		10,332,631		9,512,230
Allowance for credit losses on loans	(138,460)	(127,403)	(138,460)	(127,403)	(118,333)	(123,437)	(125,768)	(120,612)
Commercial \| Portfolio Segment Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	(230,404)		(230,404)		(232,764)
Commercial \| Portfolio Segment After Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	10,102,227		10,102,227		9,279,466
Commercial real estate
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	16,016,958		16,016,958		14,140,629
Allowance for credit losses on loans	(189,911)	(136,897)	(189,911)	(136,897)	(155,099)	(160,640)	(135,348)	(138,244)
Commercial real estate \| Portfolio Segment Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	(175,614)		(175,614)		(169,058)
Commercial real estate \| Portfolio Segment After Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	15,841,344		15,841,344		13,971,571
BBCC
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for credit losses on loans	(2,897)	(2,776)	(2,897)	(2,776)	(2,887)	(3,163)	(2,316)	(2,431)
BBCC \| Portfolio Segment Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	406,018		406,018		401,822
BBCC \| Portfolio Segment After Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	406,018		406,018		401,822
Residential real estate
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	6,894,957		6,894,957		6,699,443
Allowance for credit losses on loans	(23,135)	(20,421)	(23,135)	(20,421)	(20,837)	(21,899)	(20,207)	(21,916)
Residential real estate \| Portfolio Segment Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	0		0		0
Residential real estate \| Portfolio Segment After Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	6,894,957		6,894,957		6,699,443
Consumer
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	2,905,967		2,905,967		2,639,625
Consumer \| Portfolio Segment Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	(2,905,967)		(2,905,967)		(2,639,625)
Indirect
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	1,101,585		1,101,585		1,050,982
Allowance for credit losses on loans	(1,233)	(1,407)	(1,233)	(1,407)	(1,236)	(1,218)	(1,434)	(1,532)
Indirect \| Portfolio Segment Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	1,101,585		1,101,585		1,050,982
Indirect \| Portfolio Segment After Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	1,101,585		1,101,585		1,050,982
Direct
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	429,426		429,426		523,172
Allowance for credit losses on loans	(3,131)	(4,755)	(3,131)	(4,755)	(3,169)	(2,952)	(6,766)	(12,116)
Direct \| Portfolio Segment Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	429,426		429,426		523,172
Direct \| Portfolio Segment After Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	429,426		429,426		523,172
Home equity
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	1,374,956		1,374,956		1,065,471
Allowance for credit losses on loans	(7,568)	$ (6,896)	(7,568)	$ (6,896)	(6,049)	$ (6,404)	$ (6,872)	$ (6,820)
Home equity \| Portfolio Segment Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	1,374,956		1,374,956		1,065,471
Home equity \| Portfolio Segment After Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	1,374,956		1,374,956		1,065,471
Direct Finance Leases
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	$ 157,200		$ 157,200		$ 169,700