SHAREHOLDERS' EQUITY, Schedule of Accumulated Other Comprehensive (Loss) Income (Details) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Balance beginning of period	$ 9,432
OCI:
OCI before reclassifications and taxes	128	$ (65)
Amounts reclassified from AOCI, before tax	(5)	4
Pre-tax net OCI	123	(61)
Income tax effect	(32)	15
Total other comprehensive income/(loss), net of tax	91	(46)
Balance end of period	9,830	8,652
Accumulated other comprehensive (loss) income
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Balance beginning of period	(982)	(41)
OCI:
Balance end of period	(891)	(87)
Subtotal: net investment hedges and currency translations
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Balance beginning of period	(123)	(9)
OCI:
OCI before reclassifications and taxes	41	(1)
Amounts reclassified from AOCI, before tax	0	0
Pre-tax net OCI	41	(1)
Income tax effect	5	1
Total other comprehensive income/(loss), net of tax	46	0
Balance end of period	(77)	(9)
Net investment hedges
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Balance beginning of period	153	81
OCI:
OCI before reclassifications and taxes	(19)	(2)
Amounts reclassified from AOCI, before tax	0	0
Pre-tax net OCI	(19)	(2)
Income tax effect	5	1
Total other comprehensive income/(loss), net of tax	(14)	(1)
Balance end of period	139	80
Currency translations
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Balance beginning of period	(276)	(90)
OCI:
OCI before reclassifications and taxes	60	1
Amounts reclassified from AOCI, before tax	0	0
Pre-tax net OCI	60	1
Income tax effect	0	0
Total other comprehensive income/(loss), net of tax	60	1
Balance end of period	(216)	(89)
Available- for-sale securities
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Balance beginning of period	(902)	(5)
OCI:
OCI before reclassifications and taxes	85	(72)
Amounts reclassified from AOCI, before tax	0	0
Pre-tax net OCI	85	(72)
Income tax effect	(38)	17
Total other comprehensive income/(loss), net of tax	47	(55)
Balance end of period	(855)	(60)
Cash flow hedges
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Balance beginning of period	43	(27)
OCI:
OCI before reclassifications and taxes	2	8
Amounts reclassified from AOCI, before tax	(5)	4
Pre-tax net OCI	(3)	12
Income tax effect	1	(3)
Total other comprehensive income/(loss), net of tax	(2)	9
Balance end of period	$ 41	$ (18)