Regulatory Capital (Actual Capital Amounts and Ratios) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Compliance with Regulatory Capital Requirements for Mortgage Companies [Line Items]
Description of regulatory requirements, capital adequacy purposes	The minimum capital requirements exclude the capital conservation buffer required to avoid limitations on capital distributions, including dividend payments and certain discretionary bonus payments to executive officers. The capital conservation buffer was fully phased in during 2019. The capital conservation buffer was 2.5% at December 31, 2019. The unrealized gain or loss on available for sale securities is not included in computing regulatory capital. As of December 31, 2019, the Bank is in excess of the capital conversation buffer requirements.
Capital conversion percentage	2.5
MutualFirst Consolidated
Compliance with Regulatory Capital Requirements for Mortgage Companies [Line Items]
Tier 1 Capital to Average Total Assets		$ 2,000,000
Risk-Weighted Regulatory Capital Assets		1,500,000
MutualBank
Compliance with Regulatory Capital Requirements for Mortgage Companies [Line Items]
Leverage Capital Level, Actual Capital Levels Amount	$ 201,197	184,803
Common Equity Tier 1 Capital Level Amount	201,197	184,803
Total Risk-Based Capital Level, Actual Capital Levels Amount	214,504	198,084
Tier 1 Risk-Based Capital Level, Actual Capital Levels Amount	$ 201,197	$ 184,803
Leverage Capital Level, Actual Capital Levels Ratio	9.90%	9.20%
Common Equity Tier 1 Capital level, Actual Capital Levels Ratio	13.00%	12.10%
Total Risk-Based Capital Level, Actual Capital Levels Ratio	13.90%	13.00%
Tier 1 Risk-Based Capital Level, Actual Capital Levels Ratio	13.00%	12.10%
Leverage Capital Level, Minimum Regulatory Capital Ratios Amount	$ 80,985	$ 80,309
Common Equity Tier 1 Risk-Based Capital Level, Minimum Regulatory Capital Ratios Amount	69,574	68,476
Total Risk-Based Capital Level, Minimum Regulatory Capital Ratios Amount	123,688	121,734
Tier 1 Risk-Based Capital Level, Minimum Regulatory Capital Ratios Amount	$ 92,766	$ 91,301
Leverage Capital Level, Minimum Regulatory Capital Ratios	4.00%	4.00%
Common Equity Tier 1 Risk-Based Capital Level, Minimum Regulatory Capital Ratios	4.50%	4.50%
Total Risk-Based Capital Level, Minimum Regulatory Capital Ratios	8.00%	8.00%
Tier 1 Risk-Based Capital Level, Minimum Regulatory Capital Ratios	6.00%	6.00%
Leverage Capital Level, Minimum Required To be Considered Well-Capitalized Amount	$ 101,231	$ 100,386
Common Equity Tier 1 Risk-Based Capital Level, Minimum Required To Be Considered Well-Capitalized Amount	100,496	98,910
Total Risk-Based Capital Level, Minimum Required To be Considered Well-Capitalized Amount	154,610	152,169
Tier 1 Risk-Based Capital Level, Minimum Required To be Considered Well-Capitalized Amount	$ 123,688	$ 121,735
Leverage Capital Level, Minimum Required To be Considered Well-Capitalized Ratio	5.00%	5.00%
Common Equity Tier 1 Risk-Based Capital Level, Minimum Required To Be Considered Well-Capitalized Ratio	6.50%	6.50%
Total Risk-Based Capital Level, Minimum Required To be Considered Well-Capitalized Ratio	10.00%	10.00%
Tier 1 Risk-Based Capital Level, Minimum Required To be Considered Well-Capitalized Ratio	8.00%	8.00%
Tier 1 Capital to Average Total Assets	$ 2,000,000
Risk-Weighted Regulatory Capital Assets	$ 1,500,000