Condensed Financial Information (Parent Company Only) (Condensed Balance Sheets) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Assets
Cash on deposit with Bank	$ 22,100	$ 17,272
Cash on deposit with others	7,475	8,013
Investment in common stock of Bank	1,582	2,092
Deferred and current income tax	13,305	17,002
Other Assets	12,472	17,490
Total assets	1,424,208	1,391,405
Liabilities
Other borrowings	10,174	10,890
Other liabilities	14,735	12,861
Total liabilities	1,296,671	1,279,763
Stockholders' Equity	127,537	111,642	139,493	132,627
Total liabilities and stockholders' equity	1,424,208	1,391,405
MutualFirst Financial, Inc. [Member]
Assets
Cash on deposit with Bank	1,726	412
Cash on deposit with others	657	658
Total cash	2,383	1,070
Investment in common stock of Bank	135,264	121,362
Deferred and current income tax	149	359
Other Assets		10
Total assets	137,796	122,801
Liabilities
Other borrowings	10,174	10,890
Other liabilities	85	269
Total liabilities	10,259	11,159
Stockholders' Equity	127,537	111,642
Total liabilities and stockholders' equity	$ 137,796	$ 122,801