Investments - Maturities of Available-for-sale and Held-to-maturity Securities (Details) $ in Millions	May 12, 2019 USD ($)
Available-for-sale, Cost Basis
Due in one year or less	$ 397
Due after one year through five years	441
Due after five years	22
Available-for-sale, cost basis, total	860
Available-for-sale, Fair Value
Due in one year or less	396
Due after one year through five years	439
Due after five years	22
Available-for-sale, recorded basis, total	857
Held-to-maturity
Due in one year or less	297
Due after one year through five years	0
Due after five years	0
Held-to-maturity, cost basis, total	$ 297