Segment Reporting (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Segment Reporting Information [Line Items]
Interest income	$ 887,777	$ 797,319	$ 541,810
Total interest expense	375,581	277,992	60,512
Net interest income	512,196	519,327	481,298
Provision for credit losses on loans	9,273	15,593	23,871
Noninterest income	203,660	113,075	149,253
Salaries and employee benefits	283,768	281,768	261,654
Net occupancy and equipment	45,960	46,471	44,819
Other segment expenses	131,890	111,383	88,899
Income before income taxes	244,965	177,187	211,308
Income taxes	49,508	32,509	45,240
Net income (loss)	195,457	144,678	166,068
Total assets	18,034,868	17,360,535	16,988,176
Goodwill	988,898	991,665	991,708
Community Banks
Segment Reporting Information [Line Items]
Goodwill	988,898	988,898	988,941
Insurance
Segment Reporting Information [Line Items]
Goodwill	0	2,767	2,767
Operating Segments | Community Banks
Segment Reporting Information [Line Items]
Interest income	886,666	795,500	538,596
Total interest expense	348,199	251,026	39,562
Net interest income	538,467	544,474	499,034
Provision for credit losses on loans	9,273	15,593	23,871
Noninterest income	172,877	76,130	114,263
Salaries and employee benefits	266,639	262,325	242,360
Net occupancy and equipment	44,989	45,303	43,814
Other segment expenses	125,678	102,221	80,510
Income before income taxes	264,765	195,162	222,742
Income taxes	56,369	38,597	50,425
Net income (loss)	208,396	156,565	172,317
Total assets	18,033,458	17,313,704	16,882,534
Goodwill	988,898	988,898	988,941
Operating Segments | Insurance
Segment Reporting Information [Line Items]
Interest income	942	1,653	619
Total interest expense	0	0	0
Net interest income	942	1,653	619
Provision for credit losses on loans	0	0	0
Noninterest income	6,473	12,578	11,821
Salaries and employee benefits	3,645	7,038	7,107
Net occupancy and equipment	163	438	420
Other segment expenses	584	1,176	915
Income before income taxes	3,023	5,579	3,998
Income taxes	785	1,452	1,046
Net income (loss)	2,238	4,127	2,952
Total assets	0	40,405	37,567
Goodwill	0	2,767	2,767
Operating Segments | Wealth Management
Segment Reporting Information [Line Items]
Interest income	64	68	2,560
Total interest expense	0	0	128
Net interest income	64	68	2,432
Provision for credit losses on loans	0	0	0
Noninterest income	25,873	25,311	24,839
Salaries and employee benefits	13,484	12,405	12,187
Net occupancy and equipment	808	730	585
Other segment expenses	4,362	6,461	5,892
Income before income taxes	7,283	5,783	8,607
Income taxes	196	37	0
Net income (loss)	7,087	5,746	8,607
Total assets	3,392	6,590	75,383
Goodwill	0	0	0
Other
Segment Reporting Information [Line Items]
Interest income	105	98	35
Total interest expense	27,382	26,966	20,822
Net interest income	(27,277)	(26,868)	(20,787)
Provision for credit losses on loans	0	0	0
Noninterest income	(1,563)	(944)	(1,670)
Salaries and employee benefits	0	0	0
Net occupancy and equipment	0	0	0
Other segment expenses	1,266	1,525	1,582
Income before income taxes	(30,106)	(29,337)	(24,039)
Income taxes	(7,842)	(7,577)	(6,231)
Net income (loss)	(22,264)	(21,760)	(17,808)
Total assets	(1,982)	(164)	(7,308)
Goodwill	$ 0	$ 0	$ 0