Regulatory Capital (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Capital ($)	$ 270,062	$ 204,033
Capital to RWA (%)	12.79%	14.25%
Capital Required for Capital Adequacy ($)	$ 168,902	$ 114,576
Capital Required for Capital Adequacy to RWA (%)	8.00%	8.00%
Tier One Risk Based Capital ($)	$ 253,258	$ 189,457
Tier One Risk Based Capital to RWA (%)	11.99%	13.23%
Tier One Risk Based Capital Required for Capital Adequacy ($)	$ 126,677	$ 85,932
Tier One Risk Based Capital Required for Capital Adequacy to RWA (%)	6.00%	6.00%
Common Equity Tier One Risk Based Capital ($)	$ 229,341	$ 142,057
Common Equity Tier One Risk Based Capital To RWA (%)	10.86%	9.92%
Common Equity Tier One Risk Based Capital Required For Capital Adequacy ($)	$ 95,008	$ 64,449
Common Equity Tier One Risk Based Capital Required for Capital Adequacy to RWA (%)	4.50%	4.50%
Tier One Leverage Capital to Average Assets (%)	9.19%	9.20%
Tier One Leverage Capital Required for Capital Adequacy ($)	$ 110,242	$ 82,385
Tier One Leverage Capital Required for Capital Adequacy to Average Assets (%)	4.00%	4.00%
Subsidiaries [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Capital Required for Capital Adequacy to RWA (%)	8.00%	8.00%
Capital Required to be Well Capitalized to RWA (%)	10.00%	10.00%
Tier One Risk Based Capital Required for Capital Adequacy to RWA (%)	6.00%	6.00%
Tier One Risk Based Capital Required to be Well Capitalized to RWA (%)	8.00%	8.00%
Common Equity Tier One Risk Based Capital ($)		$ 181,361
Common Equity Tier One Risk Based Capital To RWA (%)		12.73%
Common Equity Tier One Risk Based Capital Required For Capital Adequacy ($)		$ 64,131
Common Equity Tier One Risk Based Capital Required for Capital Adequacy to RWA (%)	4.50%	4.50%
Common Equity Tier One Risk Based Capital Required to Be Well Capitalized ($)		$ 92,634
Common Equity Tier One Risk Based Capital Required To Be Well Capitalized to RiWA (%)	6.50%	6.50%
Tier One Leverage Capital Required for Capital Adequacy to Average Assets (%)	4.00%	4.00%
Tier One Leverage Capital Required to be Well Capitalized to Average Assets (%)	5.00%	5.00%
First Clover Leaf [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Capital ($)	$ 78,145
Capital to RWA (%)	15.08%
Capital Required for Capital Adequacy ($)	$ 41,459
Capital Required to be Well Capitalized ($)	51,824
Tier One Risk Based Capital ($)	$ 78,145
Tier One Risk Based Capital to RWA (%)	15.08%
Tier One Risk Based Capital Required for Capital Adequacy ($)	$ 31,094
Tier One Risk Based Capital Required to be Well Capitalized ($)	41,459
Common Equity Tier One Risk Based Capital ($)	$ 78,145
Common Equity Tier One Risk Based Capital To RWA (%)	15.08%
Common Equity Tier One Risk Based Capital Required For Capital Adequacy ($)	$ 23,321
Common Equity Tier One Risk Based Capital Required to Be Well Capitalized ($)	$ 33,685
Tier One Leverage Capital to Average Assets (%)	12.04%
Tier One Leverage Capital Required for Capital Adequacy ($)	$ 25,963
Tier One Leverage Capital Required to be Well Capitalized ($)	32,453
First Mid Bank [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Capital ($)	$ 197,552	$ 195,937
Capital to RWA (%)	12.44%	13.75%
Capital Required for Capital Adequacy ($)	$ 127,054	$ 114,012
Capital Required to be Well Capitalized ($)	158,817	142,514
Tier One Risk Based Capital ($)	$ 180,826	$ 181,361
Tier One Risk Based Capital to RWA (%)	11.39%	12.73%
Tier One Risk Based Capital Required for Capital Adequacy ($)	$ 95,290	$ 85,509
Tier One Risk Based Capital Required to be Well Capitalized ($)	127,054	$ 114,012
Common Equity Tier One Risk Based Capital ($)	$ 180,826
Common Equity Tier One Risk Based Capital To RWA (%)	11.39%
Common Equity Tier One Risk Based Capital Required For Capital Adequacy ($)	$ 71,468
Common Equity Tier One Risk Based Capital Required to Be Well Capitalized ($)	$ 103,231
Tier One Leverage Capital to Average Assets (%)	8.62%	8.83%
Tier One Leverage Capital Required for Capital Adequacy ($)	$ 83,938	$ 82,137
Tier One Leverage Capital Required to be Well Capitalized ($)	$ 104,922	$ 102,671

Common Equity Tier One Risk Based Capital as defined in the regulations.

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The amount of total capital as defined in the regulations.

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The minimum Total risk based capital ratio (total capital divided by risk weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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Total Capital divided by risk weighted assets as defined in the regulations.

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The amount of Tier 1 Leverage Capital required to be categorized as well capitalized divided by average assets as defined in the regulatory framework for prompt corrective action.

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Tier 1 Risk Based Capital as defined in the regulations.

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Tier 1 capital divided by risk weighted assets as defined by regulations.

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