Consolidated Statements of Income - USD ($) shares in Thousands		12 Months Ended
		Dec. 31, 2024		Dec. 31, 2023		Dec. 31, 2022
Interest income:
Loans, including fees		$ 369,362,000		$ 302,044,000		$ 216,138,000
Federal funds sold and interest bearing due from banks		9,256,000		8,411,000		6,018,000
Mortgage loans held for sale		232,000		211,000		190,000
Federal Home Loan Bank stock		2,306,000		1,560,000		505,000
Investment securities:
Taxable		29,896,000		32,706,000		27,302,000
Tax-exempt		1,827,000		1,764,000		1,499,000
Total interest income		412,879,000		346,696,000		251,652,000
Interest expense:
Deposits		133,541,000		81,585,000		16,412,000
Securities sold under agreements to repurchase		3,432,000		2,087,000		567,000
Federal funds purchased and other short-term borrowing		471,000		689,000		154,000
Federal Home Loan Bank advances		16,444,000		12,768,000		12,000
Subordinated debentures		1,951,000		2,235,000		1,124,000
Total interest expense		155,839,000		99,364,000		18,269,000
Net interest income		257,040,000		247,332,000		233,383,000
Provision for credit losses		9,725,000		13,796,000		10,257,000
Net interest income after provision expense		247,315,000		233,536,000		223,126,000
Non-interest income:
Mortgage banking income	[1]	3,858,000		3,705,000		3,210,000
Loss on sale of securities AFS debt securities		0	[1]	(44,000)	[1]	0
Bank owned life insurance	[1]	2,443,000		2,253,000		1,597,000
Gain (loss) on sale of premises and equipment	[1]	(100,000)		(30,000)		4,341,000
Total non-interest income		95,230,000		92,220,000		89,149,000
Non-interest expenses:
Compensation		100,842,000		91,876,000		86,640,000
Employee benefits		20,268,000		18,451,000		16,568,000
Net occupancy and equipment		15,193,000		16,384,000		14,298,000
Technology and communication		19,207,000		17,318,000		14,897,000
Debit and credit card processing		7,262,000		6,481,000		5,909,000
Marketing and business development		6,924,000		5,990,000		5,005,000
Postage, printing and supplies		3,645,000		3,604,000		3,354,000
Legal and professional		4,111,000		3,958,000		2,943,000
FDIC insurance		4,539,000		3,911,000		2,758,000
Capital and deposit based taxes		2,781,000		2,476,000		2,621,000
Intangible amortization		4,485,000		4,686,000		5,544,000
Amortization of investments in tax credit partnerships		0		1,294,000		353,000
Merger expenses		0		0		19,500,000
Loss on disposition of LFA		0		0		870,000
Other		8,922,000		11,400,000		10,531,000
Total non-interest expenses		198,179,000		187,829,000		191,791,000
Income before income tax expense		144,366,000		137,927,000		120,484,000
Income tax expense		29,827,000		30,179,000		27,190,000
Net income		114,539,000		107,748,000		93,294,000
Less net income attributed to non-controlling interest		0		0		322,000
Net income available to stockholders		$ 114,539,000		$ 107,748,000		$ 92,972,000
Net income per share - basic (in dollars per share)		$ 3.91		$ 3.69		$ 3.24
Net income per share - diluted (in dollars per share)		$ 3.89		$ 3.67		$ 3.21
Weighted average outstanding shares:
Basic (in shares)		29,288		29,212		28,672
Diluted (in shares)		29,421		29,343		28,922
Fiduciary and Trust [Member]
Non-interest income:
Non-interest income		$ 42,843,000		$ 39,802,000		$ 36,111,000
Deposit Account [Member]
Non-interest income:
Non-interest income		8,906,000		8,866,000		8,286,000
Credit and Debit Card [Member]
Non-interest income:
Non-interest income		20,082,000		19,438,000		18,623,000
Treasury Management [Member]
Non-interest income:
Non-interest income		11,064,000		10,033,000		8,590,000
Investment Advisory, Management and Administrative Service [Member]
Non-interest income:
Non-interest income		3,571,000		3,205,000		3,063,000
Product and Service, Other [Member]
Non-interest income:
Non-interest income		$ 2,563,000		$ 4,992,000		$ 5,328,000

[1] Outside of the scope of ASC 606.