Stockholders' Equity (Narrative) (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Class of Stock
Stock Repurchase Program, Authorized Amount	$ 20,000
Purchase of treasury stock	279,770	0
Purchase of treasury stock	$ 4,965	$ 741	$ 520
Proceeds from Issuance of Private Placement			40,162
Preferred stock, shares authorized	50,000	50,000
Preferred stock, shares issued	0	0
Common Stock
Class of Stock
Proceeds from Issuance of Private Placement			$ 40,162
Private Placement [Member] | Common Stock
Class of Stock
Issuance of Private Placement	1,847,826
Proceeds from Issuance of Private Placement	$ 40,200
Sale of Stock, Price Per Share	$ 23.00
NB&T Financial Group, Inc. [Member] | Common Stock
Class of Stock
Stock Issued During Period, Shares, Acquisitions	3,207,698
Stock Issued During Period, Value, Acquisitions	$ 76,000	$ 76,027