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Investment Securities - Investment Available for Sale (Details) - USD ($) $ in Millions | Sep. 30, 2022 | Dec. 31, 2021
--- | --- | ---
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | $ 86,097 | $ 94,871
Allowance for Credit Losses | (4) | (1)
Gross Unrealized Gains | 153 | 1,387
Gross Unrealized Losses | (10,943) | (996)
Securities available for sale (amortized cost of $86.1 billion and $94.9 billion and allowance for credit losses of $4 million and $1 million as of September 30, 2022 and December 31, 2021, respectively) | 75,303 | 95,261
U.S. Treasury securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 5,124 | 9,419
Allowance for Credit Losses | 0 | 0
Gross Unrealized Gains | 1 | 23
Gross Unrealized Losses | (98) | 0
Securities available for sale (amortized cost of $86.1 billion and $94.9 billion and allowance for credit losses of $4 million and $1 million as of September 30, 2022 and December 31, 2021, respectively) | 5,027 | 9,442
RMBS, Agency |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 71,245 | 72,593
Allowance for Credit Losses | 0 | 0
Gross Unrealized Gains | 37 | 958
Gross Unrealized Losses | (10,069) | (931)
Securities available for sale (amortized cost of $86.1 billion and $94.9 billion and allowance for credit losses of $4 million and $1 million as of September 30, 2022 and December 31, 2021, respectively) | 61,213 | 72,620
RMBS, Non-agency |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 666 | 792
Allowance for Credit Losses | (4) | (1)
Gross Unrealized Gains | 112 | 205
Gross Unrealized Losses | (5) | 0
Securities available for sale (amortized cost of $86.1 billion and $94.9 billion and allowance for credit losses of $4 million and $1 million as of September 30, 2022 and December 31, 2021, respectively) | 769 | 996
RMBS |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 71,911 | 73,385
Allowance for Credit Losses | (4) | (1)
Gross Unrealized Gains | 149 | 1,163
Gross Unrealized Losses | (10,074) | (931)
Securities available for sale (amortized cost of $86.1 billion and $94.9 billion and allowance for credit losses of $4 million and $1 million as of September 30, 2022 and December 31, 2021, respectively) | 61,982 | 73,616
CMBS, Agency |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 8,055 | 9,237
Allowance for Credit Losses | 0 | 0
Gross Unrealized Gains | 2 | 195
Gross Unrealized Losses | (761) | (63)
Securities available for sale (amortized cost of $86.1 billion and $94.9 billion and allowance for credit losses of $4 million and $1 million as of September 30, 2022 and December 31, 2021, respectively) | 7,296 | 9,369
Other securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 1,007 | 2,830
Allowance for Credit Losses | 0 | 0
Gross Unrealized Gains | 1 | 6
Gross Unrealized Losses | (10) | (2)
Securities available for sale (amortized cost of $86.1 billion and $94.9 billion and allowance for credit losses of $4 million and $1 million as of September 30, 2022 and December 31, 2021, respectively) | 998 | 2,834
Asset-backed Securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Securities available for sale (amortized cost of $86.1 billion and $94.9 billion and allowance for credit losses of $4 million and $1 million as of September 30, 2022 and December 31, 2021, respectively) | $ 231 | $ 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 | 98.00% | 96.00%

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