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Investment Securities - Contractual Maturities and Weighted-Average Yields of Securities (Detail) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2019 | Dec. 31, 2018
Securities available for sale |  |
Due in 1 year or less | $ 503 |
Due after 1 year through 5 years | 3,822 |
Due after 5 years through 10 years | 7,380 |
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Rolling after 10 Years, Fair Value | 67,508 |
Securities available for sale | 79,213 | $ 46,150
Amortized cost of securities available for sale |  |
Due in 1 year or less | 503 |
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Rolling after One Through Five Years, Amortized Cost | 3,816 |
Due after 5 years through 10 years | 7,334 |
Due 10 Years | 66,331 |
Amortized Cost | $ 77,984 | 46,728
Weighted average yield for securities available for sale |  |
Due in 1 Year or Less | 1.43% |
Due 1 Year through 5 Years | 2.37% |
Due 5 Years through 10 Years | 2.60% |
Due 10 Years | 3.06% |
Total weighted average yield | 2.97% |
U.S. Treasury securities |  |
Securities available for sale |  |
Due in 1 year or less | $ 0 |
Due after 1 year through 5 years | 1,476 |
Due after 5 years through 10 years | 2,648 |
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Rolling after 10 Years, Fair Value | 0 |
Securities available for sale | 4,124 | 6,144
Amortized cost of securities available for sale |  |
Amortized Cost | 4,122 | 6,146
RMBS, Agency |  |
Securities available for sale |  |
Due in 1 year or less | 0 |
Due after 1 year through 5 years | 36 |
Due after 5 years through 10 years | 891 |
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Rolling after 10 Years, Fair Value | 61,912 |
Securities available for sale | 62,839 | 31,903
Amortized cost of securities available for sale |  |
Amortized Cost | 62,003 | 32,710
RMBS, Non-agency |  |
Securities available for sale |  |
Due in 1 year or less | 0 |
Due after 1 year through 5 years | 0 |
Due after 5 years through 10 years | 0 |
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Rolling after 10 Years, Fair Value | 1,499 |
Securities available for sale | 1,499 | 1,742
Amortized cost of securities available for sale |  |
Amortized Cost | 1,235 | 1,440
RMBS |  |
Securities available for sale |  |
Due in 1 year or less | 0 |
Due after 1 year through 5 years | 36 |
Due after 5 years through 10 years | 891 |
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Rolling after 10 Years, Fair Value | 63,411 |
Securities available for sale | 64,338 | 33,645
Amortized cost of securities available for sale |  |
Amortized Cost | $ 63,238 | 34,150
Weighted average yield for securities available for sale |  |
Weighted-average expected life | 5 years 4 months 24 days |
CMBS, Agency |  |
Securities available for sale |  |
Due in 1 year or less | $ 2 |
Due after 1 year through 5 years | 1,753 |
Due after 5 years through 10 years | 3,574 |
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Rolling after 10 Years, Fair Value | 4,097 |
Securities available for sale | 9,426 | 4,739
Amortized cost of securities available for sale |  |
Amortized Cost | $ 9,303 | 4,806
Weighted average yield for securities available for sale |  |
Weighted-average expected life | 5 years 5 months |
Other securities |  |
Securities available for sale |  |
Due in 1 year or less | $ 501 |
Due after 1 year through 5 years | 557 |
Due after 5 years through 10 years | 267 |
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Rolling after 10 Years, Fair Value | 0 |
Securities available for sale | 1,325 | 1,622
Amortized cost of securities available for sale |  |
Amortized Cost | $ 1,321 | $ 1,626

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