Regulatory Matters - Summary of Capital Requirements (Details) $ in Thousands	Jun. 30, 2024 USD ($)	Dec. 31, 2023 USD ($)
BancPlus Corporation
Actual
Tier 1 Capital to Average Assets	$ 772,821	$ 756,155
Tier 1 Capital to Average Assets, ratio (as a percentage)	0.0999	0.1002
Minimum Requirement to be Well Capitalized
Tier 1 Capital to Average Assets	$ 696,358	$ 679,472
Tier 1 Capital to Average Assets, ratio (as a percentage)	0.0900	0.0900
Subsidiaries
Actual
Tier 1 Capital to Average Assets	$ 774,069	$ 755,482
Tier 1 Capital to Average Assets, ratio (as a percentage)	0.1001	0.1001
Minimum Requirement to be Well Capitalized
Tier 1 Capital to Average Assets	$ 695,955	$ 679,129
Tier 1 Capital to Average Assets, ratio (as a percentage)	0.0900	0.0900

Actual

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Minimum Requirement Phase-In Schedule

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Amount of Tier 1 leverage capital as defined by regulatory framework.

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Amount of minimum Tier 1 leverage capital required for capital adequacy as defined by regulatory framework.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 505
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477270/942-505-50-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-Section 50
-Paragraph 1B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477270/942-505-50-1B

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