Regulatory Matters (Regulatory Capital Levels) (Details) $ in Thousands	Jun. 30, 2022 USD ($)	Dec. 31, 2021 USD ($)
SmartFinancial, Inc. [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Total Capital (to Risk-Weighted Assets), Actual Amount	$ 407,413	$ 386,627
Tier 1 Capital (to Risk-Weighted Assets), Actual Amount	343,502	325,345
Common Equity Tier 1 Capital (to Risk-Weighted Assets), Actual Amount	343,502	325,345
Tier 1 Capital (to Average Assets), Actual Amount	$ 343,502	$ 325,345
Total Capital (to Risk-Weighted Assets), Actual Ratio (as a percent)	11.80	12.55
Tier 1 Capital (to Risk-Weighted Assets), Actual Ratio (as a percent)	9.95	10.56
Common Equity Tier 1 Capital (to Risk-Weighted Assets), Actual Ratio (as a percent)	9.95%	10.56%
Tier 1 Capital (to Average Assets), Actual Ratio (as a percent)	7.48	7.45
Total Capital (to Risk-Weighted Assets), Minimum for capital adequacy purposes Amount	$ 276,136	$ 246,483
Tier 1 Capital (to Risk-Weighted Assets), Minimum for capital adequacy purposes Amount	207,102	184,862
Common Equity Tier 1 Capital (to Risk-Weighted Assets), Minimum for capital adequacy purposes Amount	155,326	138,647
Tier 1 Capital (to Average Assets), Minimum for capital adequacy purposes Amount	$ 183,749	$ 174,578
Total Capital (to Risk-Weighted Assets), Minimum for capital adequacy purposes Ratio (as a percent)	8.00	8.00
Tier 1 Capital (to Risk-Weighted Assets), Minimum for capital adequacy purposes Ratio (as a percent)	6.00	6.00
Common Equity Tier 1 Capital (to Risk-Weighted Assets), Minimum for capital adequacy purposes Ratio (as a percent)	4.50%	4.50%
Tier 1 Capital (to Average Assets), Minimum for capital adequacy purposes Ratio (as a percent)	4.00	4.00
Smart Bank [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Total Capital (to Risk-Weighted Assets), Actual Amount	$ 404,412	$ 378,055
Tier 1 Capital (to Risk-Weighted Assets), Actual Amount	382,474	358,703
Common Equity Tier 1 Capital (to Risk-Weighted Assets), Actual Amount	382,474	358,703
Tier 1 Capital (to Average Assets), Actual Amount	$ 382,474	$ 358,703
Total Capital (to Risk-Weighted Assets), Actual Ratio (as a percent)	11.72	12.29
Tier 1 Capital (to Risk-Weighted Assets), Actual Ratio (as a percent)	11.08	11.66
Common Equity Tier 1 Capital (to Risk-Weighted Assets), Actual Ratio (as a percent)	11.08%	11.66%
Tier 1 Capital (to Average Assets), Actual Ratio (as a percent)	8.33	8.23
Total Capital (to Risk-Weighted Assets), Minimum for capital adequacy purposes Amount	$ 276,138	$ 246,053
Tier 1 Capital (to Risk-Weighted Assets), Minimum for capital adequacy purposes Amount	207,104	184,539
Common Equity Tier 1 Capital (to Risk-Weighted Assets), Minimum for capital adequacy purposes Amount	155,328	138,405
Tier 1 Capital (to Average Assets), Minimum for capital adequacy purposes Amount	$ 183,745	$ 174,384
Total Capital (to Risk-Weighted Assets), Minimum for capital adequacy purposes Ratio (as a percent)	8.00	8.00
Tier 1 Capital (to Risk-Weighted Assets), Minimum for capital adequacy purposes Ratio (as a percent)	6.00	6.00
Common Equity Tier 1 Capital (to Risk-Weighted Assets), Minimum for capital adequacy purposes Ratio (as a percent)	4.50%	4.50%
Tier 1 Capital (to Average Assets), Minimum for capital adequacy purposes Ratio (as a percent)	4.00	4.00
Total Capital (to Risk-Weighted Assets), Minimum to be well capitalized under prompt corrective action provisions Amount	$ 345,173	$ 307,566
Tier 1 Capital (to Risk-Weighted Assets), Minimum to be well capitalized under prompt corrective action provisions Amount	276,138	246,053
Common Equity Tier 1 Capital (to Risk-Weighted Assets), Minimum to be well capitalized under prompt corrective action provisions Amount	224,362	199,918
Tier 1 Capital (to Average Assets), Minimum to be well capitalized under prompt corrective action provisions Amount	$ 229,682	$ 217,980
Total Capital (to Risk-Weighted Assets), Minimum to be well capitalized under prompt corrective action provisions Ratio (as a percent)	10.00	10.00
Tier 1 Capital (to Risk-Weighted Assets), Minimum to be well capitalized under prompt corrective action provisions Ratio (as a percent)	8.00	8.00
Common Equity Tier 1 Capital (to Risk-Weighted Assets), Minimum to be well capitalized under prompt corrective action provisions Ratio (as a percent)	6.50%	6.50%
Tier 1 Capital (to Average Assets), Minimum to be well capitalized under prompt corrective action provisions Ratio (as a percent)	5.00	5.00

Common equity Tier 1 Risk Based Capital as defined in the regulations.

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The minimum amount of common equity Tier 1 Risk Based Capital required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The minimum common equity Tier One Capital Ratio (Common equity Tier one capital divided by risk-weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The amount of common equity Tier 1 Risk Based Capital required to be categorized as well capitalized under the regulatory framework for prompt corrective action.

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The Common equity Tier 1 capital ratio (common equity Tier 1 capital divided by risk weighted assets) required to be categorized as "well capitalized" under the regulatory framework for prompt corrective action.

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Common equity Tier 1 capital divided by risk weighted assets as defined by regulations.

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Amount of total capital as defined by regulatory framework.

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Amount of minimum total risk-based capital required for capital adequacy as defined by regulatory framework.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
-URI https://asc.fasb.org/extlink&oid=117337116&loc=SL5958568-112826

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Ratio of minimum total risk-based capital to risk-weighted assets required for capital adequacy as defined by regulatory framework.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
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-Paragraph 1B
-URI https://asc.fasb.org/extlink&oid=117337116&loc=SL5958570-112826

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-Section 50
-Paragraph 1
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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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Amount of Tier 1 leverage capital as defined by regulatory framework.

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