It represents amount of trust preferred securities qualify as Tier 1 capital.

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Face (par) amount of debt instrument at time of issuance.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

The cash outflow from the repayment of long-term borrowing where a lender is placed in a lien position behind debt having a higher priority of repayment (senior) in case of liquidation of the entity's assets before its maturity.

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- Definition

States the interest rate applicable to Federal Home Loan Bank advances outstanding as of the Balance Sheet date.

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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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Stated interest rate of the subordinated debt.

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No definition available.

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Short and Long-Term Borrowings - Narrative (Details) - USD ($)		9 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Sep. 30, 2015	Dec. 31, 2019
Debt Instrument
Short-term borrowings		$ 0		$ 0
Trust preferred securities qualify as Tier 1 capital		$ 29,800,000		$ 29,400,000
PPP Liquidity Facility (“PPPLF”) \| Minimum
Debt Instrument
Term of loan		2 years
PPP Liquidity Facility (“PPPLF”) \| Maximum
Debt Instrument
Term of loan		5 years
PPP Liquidity Facility (“PPPLF”) \| Weighted average
Debt Instrument
Term of loan		2 years
FHLB advances
Debt Instrument
FHLB weighted average interest rate		0.73%		1.57%
Junior subordinated debentures
Debt Instrument
Aggregate amount of subordinated notes		$ 38,249,000
Junior subordinated debentures \| 2004 Nicolet Bankshares Statutory Trust
Debt Instrument
Stated interest rate		8.00%
Aggregate amount of subordinated notes		$ 6,186,000
Junior subordinated debentures \| Forecast \| 2004 Nicolet Bankshares Statutory Trust
Debt Instrument
Redemption of Nicolet junior subordinated debentures	$ 6,000,000
Subordinated notes
Debt Instrument
Term of loan			10 years
Aggregate amount of subordinated notes			$ 12,000,000
Interest rate			5.00%