v3.2.0.727
Changes in Accumulated Other Comprehensive Income (Details) - USD ($)
$ in Millions
 3 Months Ended 6 Months Ended
Jun. 30, 2015
Jun. 30, 2014
Jun. 30, 2015
Jun. 30, 2014
Accumulated Other Comprehensive Income (Loss) [Line Items]        
Accumulated other comprehensive income (loss), beginning of period     $ (741)  
Accumulated other comprehensive income (loss), end of period $ (897) $ (219) (897) $ (219)
Foreign currency translation adjustments        
Accumulated Other Comprehensive Income (Loss) [Line Items]        
Accumulated other comprehensive income (loss), beginning of period (565) (27) (333) (17)
Aggregate adjustment for the period 60 19 (172) 9
Accumulated other comprehensive income (loss), end of period (505) (8) (505) (8)
Unrealized gains (losses) on derivatives        
Accumulated Other Comprehensive Income (Loss) [Line Items]        
Accumulated other comprehensive income (loss), beginning of period (82) (31) (78) 2
Other comprehensive income before reclassifications (net of tax effect) (27) 37 (50) 3
Reclassification to income (net of tax effect) 25 3 44 4
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Tax 8 10 14 3
Tax effect of reclassification to income 8 1 13 2
Accumulated other comprehensive income (loss), end of period (84) 9 (84) 9
Pension and postretirement plans        
Accumulated Other Comprehensive Income (Loss) [Line Items]        
Accumulated other comprehensive income (loss), beginning of period (303) (221) (330) (222)
Other comprehensive income before reclassifications (net of tax effect) (12) (1) 12 (2)
Reclassification to income (net of tax effect) 7 2 10 4
Tax effect of current period changes in fair value 3 1 1 1
Tax effect of reclassification to income 0 0 1 0
Accumulated other comprehensive income (loss), end of period $ (308) $ (220) $ (308) $ (220)