Goodwill and Intangible Assets Reconciliation of Purchase Price to Goodwill (Details) - USD ($) $ in Thousands		9 Months Ended
	Sep. 08, 2016	Sep. 30, 2017
Reconciliation of purchase price to goodwill recorded [Line Items]
Business Combination, Net Fair Value Adjustments	$ 10,402
Resulting goodwill from acquisition	19,143
First Clover Leaf [Member]
Reconciliation of purchase price to goodwill recorded [Line Items]
Purchase price (in excess of net book value)	8,741
Business Combination, Recognized Identifiable Assets and Liabilities Assumed, Securities	109,174
Business Combination, Recognized Identifiable Assets and Liabilities Assumed, Repossessed Assets	1,987
Fair value of premises and equipment	11,581
Fair value of time deposits	536,686
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, FHLB Advances	15,113
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Subordinated Debentures	3,269
Resulting goodwill from acquisition	19,100	$ 19,100
Goodwill Provisionally Recorded	16,800
Measurement Period Adjustment to Other Liabilities		2,000
Measurement Period Adjustment to Other Assets		$ 300
First Clover Leaf [Member] | Fair Value Adjustment [Member]
Reconciliation of purchase price to goodwill recorded [Line Items]
Business Combination, Recognized Identifiable Assets and Liabilities Assumed, Securities	737
Business Combination, Recognized Identifiable Assets and Liabilities Assumed, Loans, net	3,475
Business Combination, Recognized Identifiable Assets and Liabilities Assumed, Repossessed Assets	754
Fair value of premises and equipment	(1,963)
Fair value of time deposits	1,994
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, FHLB Advances	113
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Subordinated Debentures	(731)
Core deposit intangible	4,660
Other assets	$ 10,683