GOODWILL AND OTHER INTANGIBLE ASSETS - Rollforward of Goodwill (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 2,262,000,000	$ 2,262,000,000
Goodwill additions	215,000,000	0
Goodwill, ending balance	2,477,000,000	2,262,000,000
Community Banking
Goodwill [Roll Forward]
Goodwill, beginning balance	2,231,000,000	2,231,000,000
Goodwill additions	215,000,000	0
Goodwill, ending balance	2,446,000,000	2,231,000,000
Wealth Manage- ment
Goodwill [Roll Forward]
Goodwill, beginning balance	8,000,000	8,000,000
Goodwill additions	0	0
Goodwill, ending balance	8,000,000	8,000,000
Insurance
Goodwill [Roll Forward]
Goodwill, beginning balance	23,000,000	23,000,000
Goodwill additions	0	0
Goodwill, ending balance	$ 23,000,000	$ 23,000,000