Quarterly report pursuant to Section 13 or 15(d)

Short-term and Long-term Investments, Restricted Deposits - Fair Value of Available-For-Sale Investments with Gross Unrealized Losses by Investment Type and Length of Time (Details)

v3.20.2
Short-term and Long-term Investments, Restricted Deposits - Fair Value of Available-For-Sale Investments with Gross Unrealized Losses by Investment Type and Length of Time (Details) - USD ($)
$ in Millions
Jun. 30, 2020
Dec. 31, 2019
Unrealized Losses    
Less Than 12 Months $ (51) $ (5)
12 Months or More (7) (4)
Fair Value    
Fair Value, Less Than 12 Months 1,297 692
Fair Value, 12 Months or More 140 312
Corporate securities    
Unrealized Losses    
Less Than 12 Months (29) (2)
12 Months or More (3) (2)
Fair Value    
Fair Value, Less Than 12 Months 627 192
Fair Value, 12 Months or More 21 48
Municipal securities    
Unrealized Losses    
Less Than 12 Months (5) (1)
12 Months or More 0 0
Fair Value    
Fair Value, Less Than 12 Months 162 185
Fair Value, 12 Months or More 1 11
Asset-backed securities    
Unrealized Losses    
Less Than 12 Months (10) (1)
12 Months or More (3) (1)
Fair Value    
Fair Value, Less Than 12 Months 334 153
Fair Value, 12 Months or More 105 151
Residential mortgage-backed securities    
Unrealized Losses    
Less Than 12 Months 0 0
12 Months or More 0 (1)
Fair Value    
Fair Value, Less Than 12 Months 27 44
Fair Value, 12 Months or More 4 81
Commercial mortgage-backed securities    
Unrealized Losses    
Less Than 12 Months (7) (1)
12 Months or More (1) 0
Fair Value    
Fair Value, Less Than 12 Months 147 118
Fair Value, 12 Months or More $ 9 $ 21