FAIR VALUE MEASUREMENTS - MATURITIES FOR MARKETABLE SECURITIES (Details) $ in Millions	Sep. 30, 2017 USD ($)
Cost Basis
Due in one year or less	$ 193
Due after one year through five years	1,367
Due after five years through 10 years	36
Due after 10 years	0
Total	1,596
Fair Value
Due in one year or less	193
Due after one year through five years	1,367
Due after five years through 10 years	36
Due after 10 years	0
Total	$ 1,596