INVESTMENTS - Fair Value of AFS Debt Securities by Contractual Maturity Date (Details) - USD ($) $ in Millions	Sep. 30, 2022	Dec. 31, 2021
Fair value
Total fair value	$ 232,143	$ 288,522
Mortgage-backed securities
Amoritzed cost
Amortized cost, due within 1 year	42	188
Amortized cost, after 1 but within 5 years	514	211
Amortized cost, after 5 but within 10 years	365	523
Amortized cost, after 10 years	11,776	32,547
Amortized cost	12,697	33,469
Fair value
Fair value, due within 1 year	42	189
Fair value, after 1 but within 5 years	502	211
Fair value, after 5 but within 10 years	337	559
Fair value, after 10 years	10,930	32,662
Total fair value	11,811	33,621
U.S. Treasury and federal agency securities
Amoritzed cost
Amortized cost, due within 1 year	16,839	34,321
Amortized cost, after 1 but within 5 years	75,414	87,987
Amortized cost, after 5 but within 10 years	342	361
Amortized cost, after 10 years	0	0
Amortized cost	92,595	122,669
Fair value
Fair value, due within 1 year	16,737	34,448
Fair value, after 1 but within 5 years	72,631	87,633
Fair value, after 5 but within 10 years	295	359
Fair value, after 10 years	0	0
Total fair value	89,663	122,440
State and municipal
Amoritzed cost
Amortized cost, due within 1 year	18	40
Amortized cost, after 1 but within 5 years	101	121
Amortized cost, after 5 but within 10 years	263	156
Amortized cost, after 10 years	1,986	2,326
Amortized cost	2,368	2,643
Fair value
Fair value, due within 1 year	19	40
Fair value, after 1 but within 5 years	99	124
Fair value, after 5 but within 10 years	247	161
Fair value, after 10 years	1,788	2,296
Total fair value	2,153	2,621
Foreign government
Amoritzed cost
Amortized cost, due within 1 year	55,925	49,263
Amortized cost, after 1 but within 5 years	62,444	64,555
Amortized cost, after 5 but within 10 years	2,564	3,736
Amortized cost, after 10 years	882	1,872
Amortized cost	121,815	119,426
Fair value
Fair value, due within 1 year	55,735	49,223
Fair value, after 1 but within 5 years	60,195	63,961
Fair value, after 5 but within 10 years	2,239	3,656
Fair value, after 10 years	802	1,900
Total fair value	118,971	118,740
All other
Amoritzed cost
Amortized cost, due within 1 year	4,396	5,175
Amortized cost, after 1 but within 5 years	4,592	5,177
Amortized cost, after 5 but within 10 years	770	750
Amortized cost, after 10 years	56	54
Amortized cost	9,814	11,156
Fair value
Fair value, due within 1 year	4,378	5,180
Fair value, after 1 but within 5 years	4,420	5,149
Fair value, after 5 but within 10 years	743	750
Fair value, after 10 years	4	21
Total fair value	9,545	11,100
Debt securities AFS
Amoritzed cost
Amortized cost	239,289	289,363
Fair value
Total fair value	$ 232,143	$ 288,522