v3.19.3.a.u2
Financial Instruments - Cumulative Basis Adjustments for Fair Value Hedges (Details) - USD ($)
$ in Millions
Dec. 31, 2019
Dec. 31, 2018
Long-term investments [Member]    
Derivative [Line Items]    
Carrying Amount of Actively Hedged Assets $ 45 $ 45
Cumulative Amount of Fair Value Hedging Adjustment Increase/(Decrease) to Carrying Amount, Active Hedging Relationships, Asset 0 (1)
Cumulative Amount of Fair Value Hedging Adjustment Increase/(Decrease) to Carrying Amount, Discontinued Hedging Relationships, Asset 0 0
Short-term borrowings, including current portion of long-term debt [Member]    
Derivative [Line Items]    
Carrying Amount of Actively Hedged Liabilities 0 1,499
Cumulative Amount of Fair Value Hedging Adjustment Increase/(Decrease) to Carrying Amount, Active Hedging Relationships, Liability 0 (5)
Cumulative Amount of Fair Value Hedging Adjustment Increase/(Decrease) to Carrying Amount, Discontinued Hedging Relationships, Liability 0 0
Long-term debt [Member]    
Derivative [Line Items]    
Carrying Amount of Actively Hedged Liabilities 7,092 9,952
Cumulative Amount of Fair Value Hedging Adjustment Increase/(Decrease) to Carrying Amount, Active Hedging Relationships, Liability 266 (45)
Cumulative Amount of Fair Value Hedging Adjustment Increase/(Decrease) to Carrying Amount, Discontinued Hedging Relationships, Liability $ 690 $ 129