Consolidated Statements of Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Interest income
Interest and fees on loans	$ 411,460	$ 294,293	$ 253,131
Interest Income, Securities, Operating, Taxable	32,405	26,513	22,465
Nontaxable interest and dividends on securities	51	60	88
Interest on loans held for sale	891	159	92
Interest on federal funds sold and short-term investments	2,207	2,676	1,418
Total interest and dividend income	447,014	323,701	277,194
Interest expense
Interest on deposits	41,186	19,995	12,702
Interest on borrowings	12,693	5,541	5,632
Total interest expense	53,879	25,536	18,334
Net interest income	393,135	298,165	258,860
Provision (benefit)	6,000	4,775	2,950
Net interest income after provision for loan losses	387,135	293,390	255,910
Noninterest income
Deposit account fees	20,040	18,327	17,822
Interchange and ATM fees	22,152	18,916	17,291
Investment Banking, Advisory, Brokerage, and Underwriting Fees and Commissions	28,719	26,155	23,802
Fees and Commission Mortgage Banking	11,454	4,071	4,960
Increase in cash surrender value of life insurance policies	5,013	4,060	4,127
Gain Realized on Life Insurance Policies	434	1,463	0
Loan level derivative income	6,478	2,373	3,836
Other noninterest income	21,004	13,140	11,156
Total noninterest income	115,294	88,505	82,994
Noninterest expenses
Salaries and employee benefits	149,165	124,328	116,600
Occupancy and equipment expenses	33,207	27,098	24,693
Data processing & facilities management	6,516	5,125	4,988
FDIC assessment	1,394	2,774	3,068
Advertising expense	5,444	4,942	4,989
Consulting expense	5,448	3,891	4,038
Cost, Amortization	5,545	2,344	2,711
Debit Card Expense	4,220	3,429	3,430
Available-for-Sale Securities - Fixed Income Gross Realized Losses	1,462	0	0
Merger and acquisition expense	26,433	11,168	3,393
Software Maintenance	5,511	4,202	3,636
Other noninterest expenses	39,976	36,668	32,813
Total noninterest expenses	284,321	225,969	204,359
Income before income taxes	218,108	155,926	134,545
Provision for income taxes	52,933	34,304	47,341
Net Income	$ 165,175	$ 121,622	$ 87,204
Basic earnings per share (in dollars per share)	$ 5.03	$ 4.41	$ 3.19
Diluted earnings per share (in dollars per share)	$ 5.03	$ 4.40	$ 3.19
Weighted average common shares (basic) (in shares)	32,810,433	27,592,380	27,294,028
Common share equivalents (in shares)	45,801	61,428	78,076
Weighted average common shares (diluted) (in shares)	32,856,234	27,653,808	27,372,104
Retained Earnings
Noninterest expenses
Net Income	$ 165,175	$ 121,622	$ 87,204
Cash dividends declared (in dollars per share)	$ 1.76	$ 1.52	$ 1.28