Consolidated Statements of Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Interest and dividend income:
Loans, including fees	$ 233,721	$ 223,750	$ 186,117
Investments:
Taxable securities	27,627	39,810	33,997
Tax exempt securities	3,566	4,002	4,345
Dividends	1,032	1,285	1,705
Interest bearing cash at Federal Reserve and other banks	1,238	3,597	2,054
Total interest and dividend income	267,184	272,444	228,218
Interest expense:
Deposits	6,885	11,716	6,996
Other borrowings	17	387	2,745
Junior subordinated debt	2,555	3,272	3,131
Total interest expense	9,457	15,375	12,872
Net interest income	257,727	257,069	215,346
Provision for (benefit from) credit losses	42,813	(1,690)	2,583
Net interest income after provision for (benefit from) credit losses	214,914	258,759	212,763
Noninterest income:
Service charges and fees	37,981	40,417	38,460
Commissions on sale of non-deposit investment products	2,989	2,877	3,151
Increase in cash value of life insurance	2,949	3,029	2,718
Gain on sale of loans	9,122	3,282	2,371
Gain on sale of investment securities	7	110	207
Other	2,146	3,805	2,154
Total noninterest income	55,194	53,520	49,061
Noninterest expense:
Salaries and related benefits	112,121	106,065	93,942
Other	70,637	79,392	74,530
Total noninterest expense	182,758	185,457	168,472
Income before income taxes	87,350	126,822	93,352
Provision for income taxes	22,536	34,750	25,032
Net income	$ 64,814	$ 92,072	$ 68,320
Earnings per share:
Basic (in USD per share)	$ 2.17	$ 3.02	$ 2.57
Diluted (in USD per share)	$ 2.16	$ 3.00	$ 2.54