CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY (Parenthetical) - $ / shares	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Common Stock [Member]
Dividend reinvestment (in shares)	80,499	33,566	6,671
Stock options exercised (in shares)	11,300	39,334	18,735
Retained Earnings [Member]
Cash dividend on common stock (in dollars per share)	$ 0.40	$ 0.32	$ 0.12
Dividend reinvestment (in shares)	80,499	33,566	6,671