RETIREMENT MEDICAL PLANS (Details 2) - USD ($)	3 Months Ended	12 Months Ended
	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2013
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
APBO - beginning of year		$ 1,794,000,000
Actuarial gain		10,000,000
APBO - end of year	$ 1,794,000,000	1,656,000,000	$ 1,794,000,000
U.S. Retiree Medical Plan
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
APBO - beginning of year		477,000,000	511,000,000
Service cost		0	0	$ 1,000,000
Interest cost		19,000,000	23,000,000	21,000,000
Participant contributions		2,000,000	2,000,000
Actuarial gain		(19,000,000)	(2,000,000)
Foreign currency rate changes		(3,000,000)	(1,000,000)
Curtailment gain	(16,000,000)	0	(16,000,000)
Benefit payments		(40,000,000)	(40,000,000)
APBO - end of year	477,000,000	436,000,000	477,000,000	$ 511,000,000
Other	2,000,000	2,000,000	2,000,000
Retiree medical liability	$ 479,000,000	$ 438,000,000	$ 479,000,000