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Investment Securities - Investment Available for Sale (Details) - USD ($) $ in Millions | Mar. 31, 2023 | Dec. 31, 2022
--- | --- | ---
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | $ 90,785 | $ 87,047
Allowance for Credit Losses | (2) | (3)
Gross Unrealized Gains | 224 | 154
Gross Unrealized Losses | (9,082) | (10,279)
Securities available for sale (amortized cost of $90.8 billion and $87.0 billion and allowance for credit losses of $2 million and $3 million as of March 31, 2023 and December 31, 2022, respectively) | 81,925 | 76,919
U.S. Treasury securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 5,230 | 5,129
Allowance for Credit Losses | 0 | 0
Gross Unrealized Gains | 3 | 2
Gross Unrealized Losses | (70) | (90)
Securities available for sale (amortized cost of $90.8 billion and $87.0 billion and allowance for credit losses of $2 million and $3 million as of March 31, 2023 and December 31, 2022, respectively) | 5,163 | 5,041
RMBS, Agency |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 73,853 | 71,212
Allowance for Credit Losses | 0 | 0
Gross Unrealized Gains | 106 | 53
Gross Unrealized Losses | (8,338) | (9,413)
Securities available for sale (amortized cost of $90.8 billion and $87.0 billion and allowance for credit losses of $2 million and $3 million as of March 31, 2023 and December 31, 2022, respectively) | 65,621 | 61,852
RMBS, Non-agency |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 641 | 653
Allowance for Credit Losses | (2) | (3)
Gross Unrealized Gains | 97 | 93
Gross Unrealized Losses | (6) | (6)
Securities available for sale (amortized cost of $90.8 billion and $87.0 billion and allowance for credit losses of $2 million and $3 million as of March 31, 2023 and December 31, 2022, respectively) | 730 | 737
RMBS |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 74,494 | 71,865
Allowance for Credit Losses | (2) | (3)
Gross Unrealized Gains | 203 | 146
Gross Unrealized Losses | (8,344) | (9,419)
Securities available for sale (amortized cost of $90.8 billion and $87.0 billion and allowance for credit losses of $2 million and $3 million as of March 31, 2023 and December 31, 2022, respectively) | 66,351 | 62,589
CMBS, Agency |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 9,076 | 8,626
Allowance for Credit Losses | 0 | 0
Gross Unrealized Gains | 14 | 4
Gross Unrealized Losses | (661) | (760)
Securities available for sale (amortized cost of $90.8 billion and $87.0 billion and allowance for credit losses of $2 million and $3 million as of March 31, 2023 and December 31, 2022, respectively) | 8,429 | 7,870
Other securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 1,985 | 1,427
Allowance for Credit Losses | 0 | 0
Gross Unrealized Gains | 4 | 2
Gross Unrealized Losses | (7) | (10)
Securities available for sale (amortized cost of $90.8 billion and $87.0 billion and allowance for credit losses of $2 million and $3 million as of March 31, 2023 and December 31, 2022, respectively) | 1,982 | 1,419
Asset-backed Securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Securities available for sale (amortized cost of $90.8 billion and $87.0 billion and allowance for credit losses of $2 million and $3 million as of March 31, 2023 and December 31, 2022, respectively) | $ 1,300 | $ 707
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% | 97.00%

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