FAIR VALUE MEASUREMENTS - MATURITIES FOR MARKETABLE SECURITIES (Details) $ in Millions	Mar. 31, 2018 USD ($)
Cost Basis
Due in one year or less	$ 141
Due after one year through five years	1,207
Due after five years through 10 years	23
Total	1,371
Fair Value
Due in one year or less	141
Due after one year through five years	1,187
Due after five years through 10 years	23
Total	$ 1,351