Capital and Regulatory Matters - Actual Capital Amounts and Ratios (Details) $ in Thousands	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Origin Bancorp, Inc.
Common Equity Tier 1 Capital to Risk-Weighted Assets
Actual, amount	$ 681,039	$ 604,306
Actual, ratio	0.1120	0.0995
Minimum capital required, amount	$ 425,475	$ 425,012
Minimum capital required, ratio	7.00%	7.00%
Tier 1 Capital to Risk-Weighted Assets
Actual, amount	$ 690,448	$ 613,682
Actual, ratio	0.1136	0.1011
Minimum capital required, amount	$ 516,648	$ 516,107
Minimum capital required, ratio	0.0850	0.0850
Total Capital to Risk-Weighted Assets
Actual, amount	$ 897,503	$ 837,058
Actual, ratio	0.1477	0.1379
Minimum capital required, amount	$ 638,212	$ 637,539
Minimum capital required, ratio	0.1050	0.1050
Leverage Ratio
Actual, amount	$ 690,448	$ 613,682
Actual, ratio	0.0920	0.0862
Minimum capital required, amount	$ 300,195	$ 284,771
Minimum capital required, ratio	0.0400	0.0400
Origin Bank \| Origin Bank
Common Equity Tier 1 Capital to Risk-Weighted Assets
Actual, amount	$ 724,440	$ 637,863
Actual, ratio	0.1197	0.1053
Minimum capital required, amount	$ 423,819	$ 424,010
Minimum capital required, ratio	7.00%	7.00%
Well capitalized, amount	$ 393,546	$ 393,724
Well capitalized, ratio	6.50%	6.50%
Tier 1 Capital to Risk-Weighted Assets
Actual, amount	$ 724,440	$ 637,863
Actual, ratio	0.1197	0.1053
Minimum capital required, amount	$ 514,637	$ 514,870
Minimum capital required, ratio	0.0850	0.0850
Well capitalized, amount	$ 484,365	$ 484,583
Well capitalized, ratio	0.0800	0.0800
Total Capital to Risk-Weighted Assets
Actual, amount	$ 852,825	$ 782,503
Actual, ratio	0.1409	0.1292
Minimum capital required, amount	$ 635,727	$ 636,019
Minimum capital required, ratio	0.1050	0.1050
Well capitalized, amount	$ 605,454	$ 605,732
Well capitalized, ratio	0.1000	0.1000
Leverage Ratio
Actual, amount	$ 724,440	$ 637,863
Actual, ratio	0.0966	0.0899
Minimum capital required, amount	$ 299,932	$ 283,842
Minimum capital required, ratio	0.0400	0.0400
Well capitalized, amount	$ 374,915	$ 354,802
Well capitalized, ratio	0.0500	0.0500

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

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