Investment Securities - Securities in Gross Unrealized Loss Position (Details) $ in Millions	Dec. 31, 2022 USD ($) security	Dec. 31, 2021 USD ($) security
Debt Securities, Available-for-sale [Line Items]
Fair Value - Less than 12 Months	$ 30,629	$ 41,701
Fair Value - 12 Months or Longer	40,544	9,410
Fair Value - Total	71,173	51,111
Gross Unrealized Loss - Less than 12 Months	(2,141)	(670)
Gross Unrealized Loss - 12 Months or Longer	(8,133)	(326)
Gross Unrealized Loss - Total	$ (10,274)	$ (996)
Number of securities in gross unrealized loss positions \| security	2,840	740
U.S. Treasury securities
Debt Securities, Available-for-sale [Line Items]
Fair Value - Less than 12 Months	$ 2,464
Fair Value - 12 Months or Longer	448
Fair Value - Total	2,912
Gross Unrealized Loss - Less than 12 Months	(57)
Gross Unrealized Loss - 12 Months or Longer	(33)
Gross Unrealized Loss - Total	(90)
RMBS, Agency
Debt Securities, Available-for-sale [Line Items]
Fair Value - Less than 12 Months	23,271	$ 37,492
Fair Value - 12 Months or Longer	36,803	8,606
Fair Value - Total	60,074	46,098
Gross Unrealized Loss - Less than 12 Months	(1,809)	(632)
Gross Unrealized Loss - 12 Months or Longer	(7,604)	(299)
Gross Unrealized Loss - Total	(9,413)	(931)
RMBS, Non-agency
Debt Securities, Available-for-sale [Line Items]
Fair Value - Less than 12 Months	14	3
Fair Value - 12 Months or Longer	3	1
Fair Value - Total	17	4
Gross Unrealized Loss - Less than 12 Months	(1)	0
Gross Unrealized Loss - 12 Months or Longer	0	0
Gross Unrealized Loss - Total	(1)	0
RMBS
Debt Securities, Available-for-sale [Line Items]
Fair Value - Less than 12 Months	23,285	37,495
Fair Value - 12 Months or Longer	36,806	8,607
Fair Value - Total	60,091	46,102
Gross Unrealized Loss - Less than 12 Months	(1,810)	(632)
Gross Unrealized Loss - 12 Months or Longer	(7,604)	(299)
Gross Unrealized Loss - Total	(9,414)	(931)
CMBS, Agency
Debt Securities, Available-for-sale [Line Items]
Fair Value - Less than 12 Months	4,325	2,999
Fair Value - 12 Months or Longer	3,214	803
Fair Value - Total	7,539	3,802
Gross Unrealized Loss - Less than 12 Months	(267)	(36)
Gross Unrealized Loss - 12 Months or Longer	(493)	(27)
Gross Unrealized Loss - Total	(760)	(63)
Other securities
Debt Securities, Available-for-sale [Line Items]
Fair Value - Less than 12 Months	555	1,207
Fair Value - 12 Months or Longer	76	0
Fair Value - Total	631	1,207
Gross Unrealized Loss - Less than 12 Months	(7)	(2)
Gross Unrealized Loss - 12 Months or Longer	(3)	0
Gross Unrealized Loss - Total	$ (10)	$ (2)

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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