Consolidated Statements of Changes in Shareholders' Equity (Unaudited) (Parenthetical) (Common Stock)	6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011
Common Stock
Shares issued using employee stock purchase plan	1,217	2,193
Shares issued using stock option exercises	5,900	8,800
Number of shares tendered for stock option exercises	1,293
Shares issued using dividend reinvestment plan		644