Deferred Charges and Other Assets

12 Months Ended

Dec. 31, 2011

Deferred Charges and Other Assets [Abstract]

DEFERRED CHARGES AND OTHER ASSETS

9. DEFERRED CHARGES AND OTHER ASSETS

“Deferred charges and other assets, net” primarily includes turnaround and catalyst costs, which are deferred and amortized as discussed in Note 1. Amortization expense for deferred refinery turnaround and catalyst costs was $444 million, $383 million, and $404 million for the years ended December 31, 2011, 2010, and 2009, respectively.