Consolidated Balance Sheets (Parenthetical) (Tesoro Corporation, USD $)	Dec. 31, 2011	Dec. 31, 2010
Tesoro Corporation
STOCKHOLDERS' EQUITY
Common stock, par value	$ 0.167	$ 0.167
Common stock, authorized shares	200,000,000	200,000,000
Common stock, shares issued	150,733,991	149,105,570
Preferred stock, authorized shares	5,000,000	5,000,000
Preferred stock, shares issued	0	0
Treasury stock, common shares	10,769,510	5,925,541