SECURITIES - Amortized Cost and Fair Value of Securities, by Contractual Maturities (Detail) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Schedule Of Securities [Line Items]
Available for sale, due in one year or less, amortized cost	$ 13
Available for sale, due after one year but within five years, amortized cost	579
Available for sale, due after five year but within ten years, amortized cost	88
Available for sale, due after ten years, amortized cost	42
Available for sale, with contractual maturities, amortized cost	722
Amortized Cost	3,622	$ 3,416
Available for sale, due in one year or less, fair value	13
Available for sale, due after one year but within five years, fair value	535
Available for sale, due after five year but within ten years, fair value	87
Available for sale, due after ten years, fair value	41
Available for sale, with contractual maturities, fair value	676
Fair Value	3,275	3,426
Held to maturity, due in one year or less, amortized cost	1
Held to maturity, due after one year but within five years, amortized cost	88
Held to maturity, due after five year but within ten years, amortized cost	183
Held to maturity, due after ten years, amortized cost	818
Held to maturity, with contractual maturities, amortized cost	1,090
Amortized Cost	4,087	3,463
Held to maturity, due in one year or less, fair value	1
Held to maturity, due after one year but within five years, fair value	88
Held to maturity, due after five year but within ten years, fair value	170
Held to maturity, due after ten years, fair value	724
Held to maturity, with contractual maturities, fair value	983
Fair Value	3,687	3,506
Agency mortgage-backed securities
Schedule Of Securities [Line Items]
Available-for-sale, amortized cost	1,360
Amortized Cost	1,360	1,342
Available for sale, fair value	1,232
Fair Value	1,232	1,357
Held-to-maturity, amortized cost	1,178
Amortized Cost	1,178	1,191
Held-to-maturity, fair value	1,053
Fair Value	1,053	1,201
Agency collateralized mortgage obligations
Schedule Of Securities [Line Items]
Available-for-sale, amortized cost	1,110
Amortized Cost	1,110	1,192
Available for sale, fair value	972
Fair Value	972	1,186
Held-to-maturity, amortized cost	953
Amortized Cost	953	930
Held-to-maturity, fair value	833
Fair Value	833	923
Commercial mortgage-backed securities
Schedule Of Securities [Line Items]
Available-for-sale, amortized cost	430
Amortized Cost	430	294
Available for sale, fair value	395
Fair Value	395	297
Held-to-maturity, amortized cost	866
Amortized Cost	866	323
Held-to-maturity, fair value	818
Fair Value	$ 818	$ 324

Schedule Of Securities [Line Items]

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