INVESTMENTS - Overview (Details) - USD ($) $ in Millions		1 Months Ended	12 Months Ended
		Jun. 30, 2022	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Investment Holdings
Investments			$ 526,582	$ 512,822
Accrued interest receivable			2,000
Interest and dividends on investments
Taxable interest			10,643	6,975	$ 7,554
Interest exempt from U.S. federal income tax			348	279	301
Dividend income			223	134	134
Total interest and dividend income on investments			11,214	7,388	7,989
Gross realized investments losses, excluding losses from other-than-temporary impairment
Gross realized investment gains			323	860	1,895
Gross realized investment losses			(256)	(195)	(139)
Net realized gains on sales of investments			67	665	1,756
Securities available-for-sale
Amortized cost			255,608	289,363
Allowance for credit losses			3	8	5	$ 0
Fair value			249,679	288,522
Less than 12 months			$ 3,997	1,895
Percentage of investments gross-unrealized loss position for less than a year, rated investment grade			73.00%
12 months or longer			$ 2,607	457
Percentage of gross-unrealized loss position for a year or more rated investment grade			99.00%
Fair value of securities transferred from AFS to HTM	[1],[2]		$ 21,688	0	0
Debt securities available-for-sale (AFS)
Investment Holdings
Investments			249,679	288,522
HTM debt securities
Investment Holdings
Investments			268,863	216,963
Non-marketable equity securities measured using the measurement alternative
Investment Holdings
Investments			1,676	1,413
Mortgage-backed securities - U.S. government-sponsored agency guaranteed
Securities available-for-sale
Amortized cost			12,009	33,064
Gross unrealized gains			8	453
Gross unrealized losses			755	301
Allowance for credit losses			0	0
Fair value			11,262	33,216
Less than 12 months			412	270
12 months or longer			343	31
Fair value of securities transferred from AFS to HTM		$ 21,500
Securities transferred from AFS to HTM, unrealized loss		2,300
Mortgage-backed securities - Residential
Securities available-for-sale
Amortized cost			488	380
Gross unrealized gains			0	1
Gross unrealized losses			3	1
Allowance for credit losses			0	0
Fair value			485	380
Less than 12 months			3	1
12 months or longer			0	0
Mortgage-backed securities - Commercial
Securities available-for-sale
Amortized cost			2	25
Gross unrealized gains			0	0
Gross unrealized losses			0	0
Allowance for credit losses			0	0
Fair value			2	25
Less than 12 months			0	0
12 months or longer			0	0
Mortgage-backed securities
Securities available-for-sale
Amortized cost			12,499	33,469
Gross unrealized gains			8	454
Gross unrealized losses			758	302
Allowance for credit losses			0	0	0	0
Fair value			11,749	33,621
Less than 12 months			415	271
12 months or longer			343	31
U.S. Treasury
Securities available-for-sale
Amortized cost			94,732	122,669
Gross unrealized gains			50	615
Gross unrealized losses			2,492	844
Allowance for credit losses			0	0
Fair value			92,290	122,440
Less than 12 months			1,001	713
12 months or longer			1,491	131
Agency obligations
Securities available-for-sale
Amortized cost			0	0
Gross unrealized gains			0	0
Gross unrealized losses			0	0
Allowance for credit losses			0	0
Fair value			0	0
Less than 12 months			0	0
12 months or longer			0	0
U.S. Treasury and federal agency securities
Securities available-for-sale
Amortized cost			94,732	122,669
Gross unrealized gains			50	615
Gross unrealized losses			2,492	844
Allowance for credit losses			0	0	0	0
Fair value			92,290	122,440
Less than 12 months			1,001	713
12 months or longer			1,491	131
State and municipal
Securities available-for-sale
Amortized cost			2,363	2,643
Gross unrealized gains			19	79
Gross unrealized losses			159	101
Allowance for credit losses			0	0	0	0
Fair value			2,223	2,621
Less than 12 months			31	3
12 months or longer			128	98
Fair value of securities transferred from AFS to HTM		165
Securities transferred from AFS to HTM, unrealized loss		$ 12
Foreign government
Securities available-for-sale
Amortized cost			135,648	119,426
Gross unrealized gains			569	337
Gross unrealized losses			2,940	1,023
Allowance for credit losses			0	0	$ 0	$ 0
Fair value			133,277	118,740
Less than 12 months			2,332	826
12 months or longer			608	197
Corporate
Securities available-for-sale
Amortized cost			5,146	5,972
Gross unrealized gains			19	33
Gross unrealized losses			246	77
Allowance for credit losses			3	8
Fair value			4,916	5,920
Less than 12 months			209	77
12 months or longer			37	0
Asset-backed securities
Securities available-for-sale
Amortized cost			1,022	304
Gross unrealized gains			12	0
Gross unrealized losses			4	1
Allowance for credit losses			0	0
Fair value			1,030	303
Less than 12 months			4	1
12 months or longer			0	0
Other debt securities
Securities available-for-sale
Amortized cost			4,198	4,880
Gross unrealized gains			1	1
Gross unrealized losses			5	4
Allowance for credit losses			0	0
Fair value			4,194	4,877
Less than 12 months			5	4
12 months or longer			0	0
Debt securities
Securities available-for-sale
Amortized cost			255,608	289,363
Gross unrealized gains			678	1,519
Gross unrealized losses			6,604	2,352
Allowance for credit losses			3	8
Fair value			249,679	288,522
Fair value | Marketable equity securities
Investment Holdings
Investments			429	543
Fair value | Non-marketable equity securities
Investment Holdings
Investments			466	489
Fair value | Non-marketable equity securities measured using the measurement alternative
Investment Holdings
Alternative investment funds, fair value			27	145
Carried at cost | Non-marketable equity securities
Investment Holdings
Investments			$ 5,469	$ 4,892

[1] Operating and finance lease right-of-use assets and lease liabilities represent non-cash investing and financing activities, respectively, and are not included in the non-cash investing activities presented here. See Note 28 for more information and balances as of December 31, 2022 and 2021, respectively.

[2] See Note 2 for further information on significant disposals.