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Borrowings, Line of Credit and Subordinated Debt - Subordinated debt (Details) - USD ($) $ in Thousands		3 Months Ended	9 Months Ended	12 Months Ended
	Sep. 01, 2021	Sep. 30, 2021	Sep. 30, 2021	Dec. 31, 2020	Sep. 28, 2018
Sevier County Bancshares Inc [Member]
Debt Instrument [Line Items]
Subordinated debt	$ 2,500	$ 2,500	$ 2,500
Subordinated Debt [Member]
Debt Instrument [Line Items]
Principal amount					$ 40,000
Interest rate					5.625%
Debt issuance costs		591	591	$ 654	$ 842
Amortization expense of debt issuance costs		$ 21	$ 63
Subordinated Debt [Member] | Sevier County Bancshares Inc [Member]
Debt Instrument [Line Items]
Interest rate	6.75%
Subordinated Debt [Member] | London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Basis spread on variable rate (as a percent)				2.55%
Subordinated Debt [Member] | London Interbank Offered Rate (LIBOR) [Member] | Sevier County Bancshares Inc [Member]
Debt Instrument [Line Items]
Basis spread on variable rate (as a percent)	5.3025%

X

- Definition

Amount of subordinated debt due after one year or the normal operating cycle, if longer, assumed at the acquisition date.

+ References

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- Definition

Amount of amortization expense attributable to debt issuance costs.

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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