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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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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		12 Months Ended
	Mar. 31, 2025	Mar. 31, 2024	Dec. 31, 2024	Dec. 31, 2023
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	$ 36,413,944		$ 36,285,887
Allowance for credit losses on loans	(401,932)	$ (319,713)	(392,522)	$ (307,610)
Net loans	36,012,012		35,893,365
Taxable	515,766	487,361
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	36,413,944		36,285,887
Allowance for credit losses on loans	(401,932)		(392,522)
Net loans	36,012,012		35,893,365
Taxable	122,300		163,300
Commercial
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	10,650,615		10,288,560
Allowance for credit losses on loans	(157,587)	(123,437)	(148,722)	(118,333)
Commercial \| Portfolio Segment Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	(220,149)		(232,301)
Commercial \| Portfolio Segment After Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	10,430,466		10,056,259
Commercial real estate
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	16,135,327		16,307,486
Allowance for credit losses on loans	(198,110)	(160,640)	(200,309)	(155,099)
Commercial real estate \| Portfolio Segment Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	(173,961)		(174,438)
Commercial real estate \| Portfolio Segment After Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	15,961,366		16,133,048
BBCC
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for credit losses on loans	(2,695)	(3,163)	(2,813)	(2,887)
BBCC \| Portfolio Segment Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	394,110		406,739
BBCC \| Portfolio Segment After Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	394,110		406,739
Residential real estate
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	6,771,694		6,797,586
Allowance for credit losses on loans	(24,214)	(21,899)	(22,922)	(20,837)
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	6,771,694		6,797,586
Consumer
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	2,856,308		2,892,255
Consumer \| Portfolio Segment Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	(2,856,308)		(2,892,255)
Indirect
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	1,070,536		1,096,778
Allowance for credit losses on loans	(9,063)	(1,218)	(8,434)	(1,236)
Indirect \| Portfolio Segment Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	1,070,536		1,096,778
Indirect \| Portfolio Segment After Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	1,070,536		1,096,778
Direct
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	511,455		514,144
Allowance for credit losses on loans	(2,053)	(2,952)	(2,304)	(3,169)
Direct \| Portfolio Segment Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	511,455		514,144
Direct \| Portfolio Segment After Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	511,455		514,144
Home equity
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	1,274,317		1,281,333
Allowance for credit losses on loans	(8,210)	$ (6,404)	(7,018)	$ (6,049)
Home equity \| Portfolio Segment Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	1,274,317		1,281,333
Home equity \| Portfolio Segment After Reclassifications
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	1,274,317		1,281,333
Direct Finance Leases
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans, net of unearned income	$ 107,500		$ 120,600