Consolidated Statements of Changes in Stockholders Equity (Unaudited) (Parenthetical) (USD $)	9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011
Common stock
Common stock transactions:
Common shares purchased and retired	18,333	14,464
Common shares issued	23,973	15,440
Non-vested common shares issued	122,912	130,904
Non-vested common shares forfeited	4,689	20,039
Stock options exercised	144,346	67,197
Shares tendered in payment of option price and income tax withholding amounts	102,213	114,211
Retained earnings
Cash dividends declared:
Common (in dollars per share)	0.36	0.3375
Preferred (in dollars per share)	6.75%	6.75%