v2.4.0.6
Stockholders' equity Stockholders' equity (Details 1) (USD $)
In Millions, unless otherwise specified
3 Months Ended
Mar. 31, 2013
Increase (Decrease) in Accumulated Other Comprehensive Income [Roll Forward]  
Beginning balance, Foreign currency translation $ 12
Beginning balance, Cash flow hedges (35)
Beginning balance, Available-for-sale securities 183
Beginning balance, Other (14)
Beginning balance, AOCI 146
Other Comprehensive Income (Loss), before Tax [Abstract]  
Foreign currency translation adjustments (36)
Unrealized (losses) gains, Cash flow hedges (25)
Unrealized (losses) gains, Available-for-sale securities (32)
Unrealized (losses) gains, Other 1
Unrealized (losses) gains, AOCI (56)
Reclassification adjustments to income, Foreign currency translation 0
Reclassification adjustments to income, Cash flow hedges 144
Reclassification adjustments to income, Available-for-sale securities (67)
Reclassification adjustments to income, AOCI 77
Income taxes, Foreign currency translation 13
Income taxes, Cash flow hedges (44)
Income taxes, Available-for-sale securities 37
Income taxes, Other 0
Income taxes, AOCI (6)
Ending balance, Foreign currency translation (11)
Ending balance, Cash flow hedges 40
Ending balance, Available-for-sale securities 121
Ending balance, Other (13)
Ending balance, AOCI $ 137