Consolidated Statements of Changes in Stockholders Equity (Unaudited) (Parenthetical) - $ / shares	6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015
Common stock
Common stock transactions:
Common shares purchased and retired	995,600	588,409
Common shares issued	16,085	21,414
Non-vested common shares issued	189,624	156,956
Non-vested common shares forfeited	21,397	1,678
Stock options exercised	186,430	129,885
Shares tendered in payment of option price and income tax withholding amounts	57,153	37,567
Retained earnings
Cash dividends declared:
Common (in dollars per share)	$ 0.44	$ 0.40