Capital and Regulatory Matters - Actual Capital Amounts and Ratios (Details) $ in Thousands	Jun. 30, 2022 USD ($)	Dec. 31, 2021 USD ($)
Origin Bancorp, Inc.
Common Equity Tier 1 Capital to Risk-Weighted Assets
Actual, amount	$ 719,041	$ 681,039
Actual, ratio	0.1081	0.1120
Minimum capital required, amount	$ 465,536	$ 425,475
Minimum capital required, ratio	7.00%	7.00%
Tier 1 Capital to Risk-Weighted Assets
Actual, amount	$ 728,467	$ 690,448
Actual, ratio	0.1095	0.1136
Minimum capital required, amount	$ 565,296	$ 516,648
Minimum capital required, ratio	0.0850	0.0850
Total Capital to Risk-Weighted Assets
Actual, amount	$ 936,719	$ 897,503
Actual, ratio	0.1408	0.1477
Minimum capital required, amount	$ 698,305	$ 638,212
Minimum capital required, ratio	0.1050	0.1050
Leverage Ratio
Actual, amount	$ 728,467	$ 690,448
Actual, ratio	0.0909	0.0920
Minimum capital required, amount	$ 320,699	$ 300,195
Minimum capital required, ratio	0.0400	0.0400
Origin Bank \| Origin Bank
Common Equity Tier 1 Capital to Risk-Weighted Assets
Actual, amount	$ 757,183	$ 724,440
Actual, ratio	0.1143	0.1197
Minimum capital required, amount	$ 463,595	$ 423,819
Minimum capital required, ratio	7.00%	7.00%
Well capitalized, amount	$ 430,481	$ 393,546
Well capitalized, ratio	6.50%	6.50%
Tier 1 Capital to Risk-Weighted Assets
Actual, amount	$ 757,183	$ 724,440
Actual, ratio	0.1143	0.1197
Minimum capital required, amount	$ 562,937	$ 514,637
Minimum capital required, ratio	0.0850	0.0850
Well capitalized, amount	$ 529,823	$ 484,365
Well capitalized, ratio	0.0800	0.0800
Total Capital to Risk-Weighted Assets
Actual, amount	$ 886,705	$ 852,825
Actual, ratio	0.1339	0.1409
Minimum capital required, amount	$ 695,393	$ 635,727
Minimum capital required, ratio	0.1050	0.1050
Well capitalized, amount	$ 662,279	$ 605,454
Well capitalized, ratio	0.1000	0.1000
Leverage Ratio
Actual, amount	$ 757,183	$ 724,440
Actual, ratio	0.0947	0.0966
Minimum capital required, amount	$ 319,729	$ 299,932
Minimum capital required, ratio	0.0400	0.0400
Well capitalized, amount	$ 399,662	$ 374,915
Well capitalized, ratio	0.0500	0.0500

Common Equity Tier One Capital Required For Capital Adequacy To Risk Weighted Assets

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