SECURITIES - Schedule of Investments in Continuous Loss Positions (Details) - USD ($) $ in Millions	Mar. 31, 2026	Dec. 31, 2025
Fair Value
Less than 12 Months	$ 10,128	$ 3,415
12 Months or Longer	14,531	15,351
Total	24,659	18,766
Gross Unrealized Losses
Less than 12 Months	(253)	(164)
12 Months or Longer	(1,252)	(1,264)
Total	(1,505)	(1,428)
Mortgage-backed securities
Fair Value
Less than 12 Months	8,630	3,415
12 Months or Longer	12,547	13,361
Total	21,177	16,776
Gross Unrealized Losses
Less than 12 Months	(241)	(164)
12 Months or Longer	(1,207)	(1,214)
Total	(1,448)	(1,378)
U.S. Treasury and other
Fair Value
Less than 12 Months	1,498	0
12 Months or Longer	1,984	1,990
Total	3,482	1,990
Gross Unrealized Losses
Less than 12 Months	(12)	0
12 Months or Longer	(45)	(50)
Total	(57)	(50)
Federal agencies and U.S. government sponsored entities
Fair Value
Less than 12 Months	8,630	3,415
12 Months or Longer	12,285	13,098
Total	20,915	16,513
Gross Unrealized Losses
Less than 12 Months	(241)	(164)
12 Months or Longer	(1,204)	(1,210)
Total	(1,445)	(1,374)
Other/non-agency
Fair Value
Less than 12 Months	0	0
12 Months or Longer	262	263
Total	262	263
Gross Unrealized Losses
Less than 12 Months	0	0
12 Months or Longer	(3)	(4)
Total	$ (3)	$ (4)