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Investment Securities - Investment Available for Sale (Details) - USD ($) $ in Millions | Dec. 31, 2022 | Dec. 31, 2021
--- | --- | ---
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | $ 87,047 | $ 94,871
Allowance for Credit Losses | (3) | (1)
Gross Unrealized Gains | 154 | 1,387
Gross Unrealized Losses | (10,279) | (996)
Securities available for sale (amortized cost of $87.0 billion and $94.9 billion and allowance for credit losses of $3 million and $1 million as of December 31, 2022 and 2021, respectively) | 76,919 | 95,261
U.S. Treasury securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 5,129 | 9,419
Allowance for Credit Losses | 0 | 0
Gross Unrealized Gains | 2 | 23
Gross Unrealized Losses | (90) | 0
Securities available for sale (amortized cost of $87.0 billion and $94.9 billion and allowance for credit losses of $3 million and $1 million as of December 31, 2022 and 2021, respectively) | 5,041 | 9,442
RMBS, Agency |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 71,212 | 72,593
Allowance for Credit Losses | 0 | 0
Gross Unrealized Gains | 53 | 958
Gross Unrealized Losses | (9,413) | (931)
Securities available for sale (amortized cost of $87.0 billion and $94.9 billion and allowance for credit losses of $3 million and $1 million as of December 31, 2022 and 2021, respectively) | 61,852 | 72,620
RMBS, Non-agency |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 653 | 792
Allowance for Credit Losses | (3) | (1)
Gross Unrealized Gains | 93 | 205
Gross Unrealized Losses | (6) | 0
Securities available for sale (amortized cost of $87.0 billion and $94.9 billion and allowance for credit losses of $3 million and $1 million as of December 31, 2022 and 2021, respectively) | 737 | 996
RMBS |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 71,865 | 73,385
Allowance for Credit Losses | (3) | (1)
Gross Unrealized Gains | 146 | 1,163
Gross Unrealized Losses | (9,419) | (931)
Securities available for sale (amortized cost of $87.0 billion and $94.9 billion and allowance for credit losses of $3 million and $1 million as of December 31, 2022 and 2021, respectively) | 62,589 | 73,616
CMBS, Agency |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 8,626 | 9,237
Allowance for Credit Losses | 0 | 0
Gross Unrealized Gains | 4 | 195
Gross Unrealized Losses | (760) | (63)
Securities available for sale (amortized cost of $87.0 billion and $94.9 billion and allowance for credit losses of $3 million and $1 million as of December 31, 2022 and 2021, respectively) | 7,870 | 9,369
Other securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 1,427 | 2,830
Allowance for Credit Losses | 0 | 0
Gross Unrealized Gains | 2 | 6
Gross Unrealized Losses | (10) | (2)
Securities available for sale (amortized cost of $87.0 billion and $94.9 billion and allowance for credit losses of $3 million and $1 million as of December 31, 2022 and 2021, respectively) | 1,419 | 2,834
Asset-backed Securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Securities available for sale (amortized cost of $87.0 billion and $94.9 billion and allowance for credit losses of $3 million and $1 million as of December 31, 2022 and 2021, respectively) | $ 707 | $ 2,000
US Treasury and Agency securities | Available-for-sale securities | Government Contracts Concentration Risk |  |
Debt Securities, Available-for-sale [Line Items] |  |
Percentage of portfolio | 97.00% | 96.00%

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