Regulatory Matters - Summary of Bank's Actual Capital Amounts and Ratios (Details) $ in Thousands	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
River Financial Corporation
Summary of Bank's Actual Capital Amounts and Ratios [Lineitems]
Total Capital (To Risk-Weighted Assets), Actual Amount	$ 306,917	$ 244,657
Common Equity Tier 1 Capital (To Risk-weighted Assets), Actual Amount	237,927	180,347
Tier 1 Capital (To Risk-Weighted Assets), Actual Amount	237,927	180,347
Tier 1 Capital (To Average Assets), Actual Amount	$ 237,927	$ 180,347
Total Capital (To Risk-Weighted Assets), Actual Ratio	0.12948	0.12423
Common Equity Tier 1 Capital (To Risk-weighted Assets), Actual Ratio	10.037%	9.157%
Tier 1 Capital (To Risk-Weighted Assets), Actual ratio	0.10037	0.09157
Tier 1 Capital (To Average Assets), Actual Ratio	0.07505	0.06722
Total Capital (To Risk-Weighted Assets), Required For Capital Adequacy Purposes Amount	$ 248,890	$ 206,786
Common Equity Tier 1 Capital (To Risk-weighted Assets), Required For Capital Adequacy Purposes Amount	165,935	137,865
Tier 1 Capital (To Average Assets), Required For Capital Adequacy Purposes Amount	$ 126,810	$ 107,317
Total Capital (To Risk-Weighted Assets) Required For Capital Adequacy Purposes Ratio	0.105	0.105
Common Equity Tier 1 Capital (To Risk-weighted Assets), Required For Capital Adequacy Purposes Ratio	7.00%	7.00%
Tier 1 Capital (To Risk-Weighted Assets), Required For Capital Adequacy Purposes Amount	$ 201,492	$ 167,407
Tier 1 Capital (To Risk-Weighted Assets), Required For Capital Adequacy Purposes Ratio	0.085	0.085
Tier 1 Capital (To Average Assets), Required For Capital Adequacy Purposes Ratio	0.04	0.04
River Bank
Summary of Bank's Actual Capital Amounts and Ratios [Lineitems]
Total Capital (To Risk-Weighted Assets), Actual Amount	$ 303,279	$ 242,168
Common Equity Tier 1 Capital (To Risk-weighted Assets), Actual Amount	274,289	217,858
Tier 1 Capital (To Risk-Weighted Assets), Actual Amount	274,289	217,858
Tier 1 Capital (To Average Assets), Actual Amount	$ 274,289	$ 217,858
Total Capital (To Risk-Weighted Assets), Actual Ratio	0.12794	0.12296
Common Equity Tier 1 Capital (To Risk-weighted Assets), Actual Ratio	11.571%	11.062%
Tier 1 Capital (To Risk-Weighted Assets), Actual ratio	0.11571	0.11062
Tier 1 Capital (To Average Assets), Actual Ratio	0.08652	0.08120
Total Capital (To Risk-Weighted Assets), Required For Capital Adequacy Purposes Amount	$ 248,892	$ 206,789
Common Equity Tier 1 Capital (To Risk-weighted Assets), Required For Capital Adequacy Purposes Amount	165,928	137,860
Tier 1 Capital (To Average Assets), Required For Capital Adequacy Purposes Amount	$ 126,807	$ 107,315
Total Capital (To Risk-Weighted Assets) Required For Capital Adequacy Purposes Ratio	0.105	0.105
Common Equity Tier 1 Capital (To Risk-weighted Assets), Required For Capital Adequacy Purposes Ratio	7.00%	7.00%
Tier 1 Capital (To Risk-Weighted Assets), Required For Capital Adequacy Purposes Amount	$ 201,484	$ 167,401
Tier 1 Capital (To Risk-Weighted Assets), Required For Capital Adequacy Purposes Ratio	0.085	0.085
Tier 1 Capital (To Average Assets), Required For Capital Adequacy Purposes Ratio	0.04	0.04
Total Capital (To Risk-Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Regulations, Amount	$ 237,040	$ 196,942
Common Equity Tier 1 Capital (To Risk-weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Regulations, Amount	154,076	128,013
Tier 1 Capital (To Risk-Weighted Assets),To Be Well Capitalized Under Prompt Corrective Action Regulations, Amount	189,632	157,554
Tier 1 Capital (To Average Assets), To Be Well Capitalized Under Prompt Corrective Action Regulations, Amount	$ 158,508	$ 134,144
Total Capital (To Risk-Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Regulations, Ratio	0.10	0.10
Common Equity Tier 1 Capital (To Risk-weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Regulations, Ratio	6.50%	6.50%
Tier 1 Capital (To Risk-Weighted Assets), To Be Well Capitalized Under Prompt Corrective Action Regulations, Ratio	0.08	0.08
Tier 1 Capital (To Average Assets).To Be Well Capitalized Under Prompt Corrective Action Regulations, Ratio	0.05	0.05

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Tier one risk based capital required for capital adequacy with buffer.

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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
-Topic 942
-SubTopic 505
-Name Accounting Standards Codification
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