SEGMENT INFORMATION, Classified by Major Geographic Areas (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Sep. 30, 2019
Revenues:
Total net revenues	$ 1,834	$ 1,927	$ 5,911	$ 5,717
Pre-tax income
Total pre-tax income	198	342	796	1,021
Total assets:
Total assets	44,682		44,682		$ 38,830
Goodwill:
Goodwill	465		465		464
U.S.
Revenues:
Total net revenues	1,706	1,793	5,501	5,318
Pre-tax income
Total pre-tax income	191	330	770	994
Total assets:
Total assets	41,459		41,459		35,978
Goodwill:
Goodwill	433		433		433
Canada
Revenues:
Total net revenues	86	101	293	290
Pre-tax income
Total pre-tax income	5	12	26	35
Total assets:
Total assets	3,099		3,099		2,754
Goodwill:
Goodwill	24		24		23
Europe
Revenues:
Total net revenues	42	33	117	109
Pre-tax income
Total pre-tax income	2	$ 0	0	(8)
Disposition-related expenses for loss on sale of operations				$ 15
Total assets:
Total assets	124		124		98
Goodwill:
Goodwill	$ 8		$ 8		$ 8