SCHEDULE II — VALUATION AND QUALIFYING ACCOUNTS (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Allowance for doubtful accounts
Valuation and Qualifying Account
Balance at beginning of year	$ 32	$ 35	$ 27
Charged (credited) to costs and expenses	32	29	36
Other	(22)	(32)	(28)
Balance at end of year	42	32	35
Deferred tax assets valuation allowance
Valuation and Qualifying Account
Balance at beginning of year	91	117	107
Charged (credited) to costs and expenses	0	(26)	10
Other	14	0	0
Balance at end of year	$ 105	$ 91	$ 117