RISK MANAGEMENT ACTIVITIES AND FAIR VALUE MEASUREMENTS - LIABILITIES - ADDITIONAL INFORMATION (Details) - USD ($) $ in Millions	Jun. 30, 2017	Jun. 30, 2016
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term Debt, Fair Value	$ 21,396	$ 24,362
Long Term Debt, Current Maturities Measured at Fair Value	1,694	2,761
Fair Value, Inputs, Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term Debt, Fair Value	$ 1,716	$ 2,331