GOODWILL - Narrative (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2023 USD ($)	Sep. 30, 2022 USD ($)	Sep. 30, 2023 USD ($) segment	Sep. 30, 2022 USD ($)	Dec. 31, 2022 USD ($)
Goodwill [Line Items]
Number of reporting units | segment			2
Goodwill impairment loss			$ 0
Consumer Banking
Goodwill [Line Items]
Goodwill impairment loss	$ 0	$ 0	0	$ 0
Goodwill accumulated impairment loss	5,900,000,000		5,900,000,000		$ 5,900,000,000
Commercial Banking
Goodwill [Line Items]
Goodwill impairment loss	0	$ 0	0	$ 0
Goodwill accumulated impairment loss	$ 50,000,000		$ 50,000,000		$ 50,000,000