RETIREMENT MEDICAL PLANS (Details 5) - U.S. Retiree Medical Plan - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2013
Service cost		$ 0	$ 0	$ 1
Interest cost		19	23	21
Amortization of - Prior service cost (benefit)		(1)	(7)	(8)
Actuarial losses		22	23	27
Recognized prior service costs due to curtailment	$ (15)	0	(15)	0
Retiree medical expense - total company		$ 40	$ 24	$ 41