Annual report pursuant to Section 13 and 15(d)

Employee Benefit Plans (Details)

v2.4.0.6
Employee Benefit Plans (Details) (USD $)
In Millions, unless otherwise specified
12 Months Ended
Dec. 31, 2011
Dec. 31, 2010
Dec. 31, 2009
Employee Benefit Plans [Abstract]      
Defined Contribution Plan, Cost Recognized $ 18 $ 16 $ 18