Consolidated Balance Sheets (Parenthetical)	Dec. 31, 2011	Dec. 31, 2010
Consolidated Balance Sheets
Preferred stock, authorized shares	10,000,000	10,000,000
Preferred stock, issued shares	0	0
Common stock, authorized shares	200,000,000	200,000,000
Common stock, issued shares	96,038,328	94,690,932
Common stock, outstanding shares	96,038,328	94,690,932