XML 15 R4.htm IDEA: XBRL DOCUMENT v2.3.0.15
Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) (USD $)
In Millions
Sep. 30, 2011
Dec. 31, 2010
Current Assets:  
Reserves on receivables$ 17$ 17
Accumulated depreciation and depletion on property, plant and equipment$ 1,590$ 1,546