Regulatory Matters (Regulatory Capital Levels) (Details) $ in Thousands	Mar. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
SmartFinancial, Inc. [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Total Capital (to Risk-Weighted Assets), Actual Amount	$ 438,163	$ 425,957
Tier 1 Capital (to Risk-Weighted Assets), Actual Amount	370,339	360,608
Common Equity Tier 1 Capital (to Risk-Weighted Assets), Actual Amount	370,339	360,608
Tier 1 Capital (to Average Assets), Actual Amount	$ 370,339	$ 360,608
Total Capital (to Risk-Weighted Assets), Actual Ratio (as a percent)	0.1177	0.1140
Tier 1 Capital (to Risk-Weighted Assets), Actual Ratio (as a percent)	0.0995	0.0965
Common Equity Tier 1 Capital (to Risk-Weighted Assets), Actual Ration (as percent)	0.0995	0.0965
Tier 1 Capital (to Average Assets), Actual Ratio (as a percent)	0.0791	0.0795
Total Capital (to Risk-Weighted Assets), Minimum for capital adequacy purposes Amount	$ 297,854	$ 298,966
Tier 1 Capital (to Risk-Weighted Assets), Minimum for capital adequacy purposes Amount	223,391	224,224
Common Equity Tier 1 Capital (to Risk-Weighted Assets), Minimum for capital adequacy purposes Amount	167,543	168,168
Tier 1 Capital (to Average Assets), Minimum for capital adequacy purposes Amount	$ 187,364	$ 181,387
Total Capital (to Risk-Weighted Assets), Minimum for capital adequacy purposes Ratio (as a percent)	0.0800	0.0800
Tier 1 Capital (to Risk-Weighted Assets), Minimum for capital adequacy purposes Ratio (as a percent)	0.0600	0.0600
Common Equity Tier 1 Capital (to Risk-Weighted Assets), Minimum for capital adequacy purposes Ratio (as a percent)	0.0450	0.0450
Tier 1 Capital (to Average Assets), Minimum for capital adequacy purposes Ratio (as a percent)	0.0400	0.0400
Smart Bank [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Total Capital (to Risk-Weighted Assets), Actual Amount	$ 441,097	$ 426,947
Tier 1 Capital (to Risk-Weighted Assets), Actual Amount	415,309	403,613
Common Equity Tier 1 Capital (to Risk-Weighted Assets), Actual Amount	415,309	403,613
Tier 1 Capital (to Average Assets), Actual Amount	$ 415,309	$ 403,613
Total Capital (to Risk-Weighted Assets), Actual Ratio (as a percent)	0.1185	0.1144
Tier 1 Capital (to Risk-Weighted Assets), Actual Ratio (as a percent)	0.1115	0.1082
Common Equity Tier 1 Capital (to Risk-Weighted Assets), Actual Ration (as percent)	0.1115	0.1082
Tier 1 Capital (to Average Assets), Actual Ratio (as a percent)	0.0887	0.0890
Total Capital (to Risk-Weighted Assets), Minimum for capital adequacy purposes Amount	$ 297,853	$ 298,476
Tier 1 Capital (to Risk-Weighted Assets), Minimum for capital adequacy purposes Amount	223,390	223,857
Common Equity Tier 1 Capital (to Risk-Weighted Assets), Minimum for capital adequacy purposes Amount	167,542	167,892
Tier 1 Capital (to Average Assets), Minimum for capital adequacy purposes Amount	$ 187,358	$ 181,383
Total Capital (to Risk-Weighted Assets), Minimum for capital adequacy purposes Ratio (as a percent)	0.0800	0.0800
Tier 1 Capital (to Risk-Weighted Assets), Minimum for capital adequacy purposes Ratio (as a percent)	0.0600	0.0600
Common Equity Tier 1 Capital (to Risk-Weighted Assets), Minimum for capital adequacy purposes Ratio (as a percent)	0.0450	0.0450
Tier 1 Capital (to Average Assets), Minimum for capital adequacy purposes Ratio (as a percent)	0.0400	0.0400
Total Capital (to Risk-Weighted Assets), Minimum to be well capitalized under prompt corrective action provisions Amount	$ 372,316	$ 373,094
Tier 1 Capital (to Risk-Weighted Assets), Minimum to be well capitalized under prompt corrective action provisions Amount	297,853	298,476
Common Equity Tier 1 Capital (to Risk-Weighted Assets), Minimum to be well capitalized under prompt corrective action provisions Amount	242,005	242,511
Tier 1 Capital (to Average Assets), Minimum to be well capitalized under prompt corrective action provisions Amount	$ 234,198	$ 226,729
Total Capital (to Risk-Weighted Assets), Minimum to be well capitalized under prompt corrective action provisions Ratio (as a percent)	0.1000	0.1000
Tier 1 Capital (to Risk-Weighted Assets), Minimum to be well capitalized under prompt corrective action provisions Ratio (as a percent)	0.0800	0.0800
Common Equity Tier 1 Capital (to Risk-Weighted Assets), Minimum to be well capitalized under prompt corrective action provisions Ratio (as a percent)	0.0650	0.0650
Tier 1 Capital (to Average Assets), Minimum to be well capitalized under prompt corrective action provisions Ratio (as a percent)	0.0500	0.0500