XML 44 R51.htm IDEA: XBRL DOCUMENT  v2.3.0.11
Debt (Revolving Credit Facility And Commercial Paper) (Details) (USD $)
6 Months Ended
Jun. 30, 2011
Dec. 31, 2010
Jun. 30, 2011
Commercial Paper [Member]
Jun. 30, 2011
Syndicated Revolving Credit Facility [Member]
Jun. 30, 2011
Standby Letters Of Credit [Member]
Amount available for borrowing       $ 665,000,000  
Amount available for borrowing     665,000,000    
Amount available for borrowing, commercial paper         100,000,000
Revolving credit facility expiration date       November 2012  
Outstanding borrowings under the facility 0        
Outstanding commercial paper obligations 111,900,000 34,000,000      
Standby letters of credit outstanding         $ 0