Consolidated Statements of Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Interest income:
Loans, including loan fees	$ 33,766	$ 31,209	$ 67,544	$ 61,177
Investment securities:
Taxable	2,042	2,041	4,114	3,674
Tax-exempt	509	522	1,000	1,071
Other interest income	575	798	1,237	1,807
Total interest income	36,892	34,570	73,895	67,729
Interest expense:
Deposits	4,455	4,730	9,412	9,507
Short-term borrowings	38	0	65	0
Long-term borrowings	902	896	1,658	1,803
Total interest expense	5,395	5,626	11,135	11,310
Net interest income	31,497	28,944	62,760	56,419
Provision for credit losses	3,000	300	6,000	500
Net interest income after provision for credit losses	28,497	28,644	56,760	55,919
Noninterest income:
Mortgage income, net	9,963	2,059	12,290	3,262
BOLI income	540	880	1,243	1,339
Asset gains (losses), net	(748)	7,572	(1,402)	7,744
Other income	1,487	1,624	2,008	3,108
Total noninterest income	17,471	18,560	27,056	27,746
Noninterest expense:
Personnel	14,482	15,358	27,805	27,895
Occupancy, equipment and office	4,361	3,757	8,565	7,507
Business development and marketing	2,514	1,579	3,873	2,860
Data processing	2,399	2,350	4,962	4,705
Intangibles amortization	880	969	1,873	2,022
Other expense	3,177	1,714	4,589	3,497
Total noninterest expense	27,813	25,727	51,667	48,486
Income before income tax expense	18,155	21,477	32,149	35,179
Income tax expense	4,576	2,833	7,897	6,185
Net income	13,579	18,644	24,252	28,994
Less: Net income attributable to noncontrolling interest	101	95	219	178
Net income attributable to Nicolet Bankshares, Inc.	$ 13,478	$ 18,549	$ 24,033	$ 28,816
Earnings per common share:
Basic (in dollars per share)	$ 1.29	$ 1.98	$ 2.30	$ 3.06
Diluted (in dollars per share)	$ 1.28	$ 1.91	$ 2.25	$ 2.97
Weighted average common shares outstanding:
Basic (in shares)	10,417,226	9,374,348	10,466,590	9,417,676
Diluted (in shares)	10,519,739	9,692,378	10,659,318	9,710,827
Trust services fee income
Noninterest income:
Fees and commissions	$ 1,510	$ 1,569	$ 3,089	$ 3,037
Brokerage fee income
Noninterest income:
Fees and commissions	2,269	2,002	4,591	3,812
Service charges on deposit accounts
Noninterest income:
Fees and commissions	813	1,194	2,038	2,364
Card interchange income
Noninterest income:
Fees and commissions	$ 1,637	$ 1,660	$ 3,199	$ 3,080