Regulatory Capital - Schedule of Compliance with Regulatory Capital Requirements under Banking Regulations (Details) $ in Thousands	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Phantom section (for regulatory ratios):
Capital ($)	$ 801,966	$ 674,310
Capital to RWA (%)	0.1520	0.1579
Capital Required for Capital Adequacy ($)	$ 554,164	$ 448,344
Capital Required for Capital Adequacy to RWA (%)	0.1050	0.1050
Tier One Risk Based Capital ($)	$ 654,453	$ 534,277
Tier One Risk Based Capital to RWA (%)	0.1240	0.1251
Tier One Risk Based Capital Required for Capital Adequacy ($)	$ 448,609	$ 362,945
Tier One Risk Based Capital Required for Capital Adequacy to RWA (%)	0.0850	0.0850
Common Equity Tier One Risk Based Capital ($)	$ 635,089	$ 515,082
Common Equity Tier One Risk Based Capital To RWA (%)	0.1203	0.1206
Common Equity Tier One Risk Based Capital Required For Capital Adequacy ($)	$ 369,442	$ 298,896
Common Equity Tier One Risk Based Capital Required for Capital Adequacy to RWA (%)	0.0700	0.0700
Tier One Leverage Capital to Average Assets	$ 654,453	$ 534,277
Tier One Leverage Capital to Average Assets (%)	0.0968	0.0905
Tier One Leverage Capital Required for Capital Adequacy ($)	$ 268,875	$ 236,151
Tier One Leverage Capital Required for Capital Adequacy to Average Assets (%)	0.0400	0.0400
First Mid Bank
Phantom section (for regulatory ratios):
Capital ($)	$ 745,624	$ 624,150
Capital to RWA (%)	0.1418	0.1467
Capital Required for Capital Adequacy ($)	$ 552,161	$ 446,711
Capital Required for Capital Adequacy to RWA (%)	0.1050	0.1050
Capital Required to be Well Capitalized ($)	$ 525,868	$ 425,439
Capital Required to be Well Capitalized to RWA (%)	0.1000	0.1000
Tier One Risk Based Capital ($)	$ 692,664	$ 578,517
Tier One Risk Based Capital to RWA (%)	0.1317	0.1360
Tier One Risk Based Capital Required for Capital Adequacy with Capital Buffer ($)	$ 446,987	$ 361,623
Tier One Risk Based Capital Required for Capital Adequacy with Capital Buffer to RWA (%)	0.0850	0.0850
Tier One Risk Based Capital Required to be Well Capitalized ($)	$ 420,694	$ 340,351
Tier One Risk Based Capital Required to be Well Capitalized to RWA (%)	0.0800	0.0800
Common Equity Tier One Risk Based Capital ($)	$ 692,664	$ 578,517
Common Equity Tier One Risk Based Capital To RWA (%)	0.1317	0.1360
Common Equity Tier One Risk Based Capital Required For Capital Adequacy ($)	$ 368,107	$ 297,807
Common Equity Tier One Risk Based Capital Required for Capital Adequacy to RWA (%)	0.0700	0.0700
Common Equity Tier One Risk Based Capital Required to Be Well Capitalized ($)	$ 341,814	$ 276,535
Common Equity Tier One Risk Based Capital Required To Be Well Capitalized to RiWA (%)	0.0650	0.0650
Tier One Leverage Capital to Average Assets	$ 692,664	$ 578,517
Tier One Leverage Capital to Average Assets (%)	0.1022	0.0983
Tier One Leverage Capital Required for Capital Adequacy ($)	$ 270,990	$ 235,337
Tier One Leverage Capital Required for Capital Adequacy to Average Assets (%)	0.0400	0.0400
Tier One Leverage Capital Required to be Well Capitalized ($)	$ 338,738	$ 294,171
Tier One Leverage Capital Required to be Well Capitalized to Average Assets (%)	0.0500	0.0500

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

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Ratio of minimum Common Equity Tier 1 risk-based capital to risk-weighted assets required for capital adequacy as defined by regulatory framework.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 505
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