Loans and Allowance for Credit Losses (Allowance for Credit Losses by Portfolio Class) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses: Beginning balance	$ 307,907	$ 307,789	$ 342,065
Allowance for loan losses: Net provision for loan losses	52,167	59,103	(28,399)
Allowance for loan losses: Ending balance	318,882	307,907	307,789
Reserve for unfunded lending commitments: Beginning balance	28,894	33,309	29,334
Reserve for unfunded lending commitments: Provision for losses	(4,841)	(4,415)	3,975
Reserve for unfunded lending commitments: Ending balance	24,053	28,894	33,309
Total allowance for credit losses	342,935	336,801	341,098
Allowance for credit losses: Individually evaluated	9,620	1,666	476
Allowance for credit losses: Collectively evaluated	333,315	335,135	340,622
Non-Purchased Credit Impaired Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses: Charge-offs	(73,084)	(75,423)	(22,590)
Allowance for loan losses: Recoveries	27,051	12,023	20,688
Allowance for loan losses: Net provision for loan losses	57,008	63,518	(32,374)
Total Commercial [Member] | Commercial Real Estate - Income Producing [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses: Beginning balance	74,539	71,961	108,058
Allowance for loan losses: Ending balance	71,975	74,539	71,961
Reserve for unfunded lending commitments: Beginning balance	1,344	1,395	1,694
Reserve for unfunded lending commitments: Provision for losses	(702)	(51)	(299)
Reserve for unfunded lending commitments: Ending balance	642	1,344	1,395
Total allowance for credit losses	72,617	75,883	73,356
Allowance for credit losses: Individually evaluated			16
Allowance for credit losses: Collectively evaluated	72,617	75,883	73,340
Total Commercial [Member] | Construction and Land Development [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses: Beginning balance	27,039	30,498	22,102
Allowance for loan losses: Ending balance	21,158	27,039	30,498
Reserve for unfunded lending commitments: Beginning balance	20,019	25,110	21,907
Reserve for unfunded lending commitments: Provision for losses	(5,380)	(5,091)	3,203
Reserve for unfunded lending commitments: Ending balance	14,639	20,019	25,110
Total allowance for credit losses	35,797	47,058	55,608
Allowance for credit losses: Individually evaluated			18
Allowance for credit losses: Collectively evaluated	35,797	47,058	55,590
Total Commercial [Member] | Non-Purchased Credit Impaired Loans [Member] | Commercial Real Estate - Income Producing [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses: Charge-offs	(8,822)	(73)	(1,073)
Allowance for loan losses: Recoveries	7	14	878
Allowance for loan losses: Net provision for loan losses	6,251	2,637	(35,902)
Total Commercial [Member] | Non-Purchased Credit Impaired Loans [Member] | Construction and Land Development [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses: Charge-offs	(264)	(72)	(3)
Allowance for loan losses: Recoveries	64	11	134
Allowance for loan losses: Net provision for loan losses	(5,681)	(3,398)	8,265
Total Commercial [Member] | Total Commercial And Industrial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses: Beginning balance	141,934	144,745	149,321
Allowance for loan losses: Ending balance	157,354	141,934	144,745
Reserve for unfunded lending commitments: Beginning balance	5,834	5,286	4,845
Reserve for unfunded lending commitments: Provision for losses	916	548	441
Reserve for unfunded lending commitments: Ending balance	6,750	5,834	5,286
Total allowance for credit losses	164,104	147,768	150,031
Allowance for credit losses: Individually evaluated	8,672	1,666	102
Allowance for credit losses: Collectively evaluated	155,432	146,102	149,929
Total Commercial [Member] | Total Commercial And Industrial [Member] | Commercial Non-Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses: Beginning balance	101,737	96,461	95,888
Allowance for loan losses: Ending balance	121,090	101,737	96,461
Reserve for unfunded lending commitments: Beginning balance	5,507	4,984	4,522
Reserve for unfunded lending commitments: Provision for losses	934	523	462
Reserve for unfunded lending commitments: Ending balance	6,441	5,507	4,984
Total allowance for credit losses	127,531	107,244	101,445
Allowance for credit losses: Individually evaluated	8,672	1,666	71
Allowance for credit losses: Collectively evaluated	118,859	105,578	101,374
Total Commercial [Member] | Total Commercial And Industrial [Member] | Commercial Real Estate - Owner Occupied
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses: Beginning balance	40,197	48,284	53,433
Allowance for loan losses: Ending balance	36,264	40,197	48,284
Reserve for unfunded lending commitments: Beginning balance	327	302	323
Reserve for unfunded lending commitments: Provision for losses	(18)	25	(21)
Reserve for unfunded lending commitments: Ending balance	309	327	302
Total allowance for credit losses	36,573	40,524	48,586
Allowance for credit losses: Individually evaluated			31
Allowance for credit losses: Collectively evaluated	36,573	40,524	48,555
Total Commercial [Member] | Total Commercial And Industrial [Member] | Non-Purchased Credit Impaired Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses: Charge-offs	(45,631)	(59,830)	(8,585)
Allowance for loan losses: Recoveries	23,328	7,109	12,545
Allowance for loan losses: Net provision for loan losses	37,723	49,910	(8,536)
Total Commercial [Member] | Total Commercial And Industrial [Member] | Non-Purchased Credit Impaired Loans [Member] | Commercial Non-Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses: Charge-offs	(45,488)	(59,830)	(7,637)
Allowance for loan losses: Recoveries	22,292	6,152	11,812
Allowance for loan losses: Net provision for loan losses	42,549	58,954	(3,602)
Total Commercial [Member] | Total Commercial And Industrial [Member] | Non-Purchased Credit Impaired Loans [Member] | Commercial Real Estate - Owner Occupied
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses: Charge-offs	(143)		(948)
Allowance for loan losses: Recoveries	1,036	957	733
Allowance for loan losses: Net provision for loan losses	(4,826)	(9,044)	(4,934)
Residential Mortgages [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses: Beginning balance	38,983	32,464	30,623
Allowance for loan losses: Ending balance	42,445	38,983	32,464
Reserve for unfunded lending commitments: Beginning balance	30	31	22
Reserve for unfunded lending commitments: Provision for losses	(26)	(1)	9
Reserve for unfunded lending commitments: Ending balance	4	30	31
Total allowance for credit losses	42,449	39,013	32,495
Allowance for credit losses: Individually evaluated	751		239
Allowance for credit losses: Collectively evaluated	41,698	39,013	32,256
Residential Mortgages [Member] | Non-Purchased Credit Impaired Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses: Charge-offs	(380)	(55)	(137)
Allowance for loan losses: Recoveries	595	1,278	1,749
Allowance for loan losses: Net provision for loan losses	3,247	5,296	229
Consumer [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses: Beginning balance	25,412	28,121	31,961
Allowance for loan losses: Ending balance	25,950	25,412	28,121
Reserve for unfunded lending commitments: Beginning balance	1,667	1,487	866
Reserve for unfunded lending commitments: Provision for losses	351	180	621
Reserve for unfunded lending commitments: Ending balance	2,018	1,667	1,487
Total allowance for credit losses	27,968	27,079	29,608
Allowance for credit losses: Individually evaluated	197		101
Allowance for credit losses: Collectively evaluated	27,771	27,079	29,507
Consumer [Member] | Non-Purchased Credit Impaired Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses: Charge-offs	(17,987)	(15,393)	(12,792)
Allowance for loan losses: Recoveries	3,057	3,611	5,382
Allowance for loan losses: Net provision for loan losses	$ 15,468	$ 9,073	$ 3,570