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Investment Securities (Investments Classified by Contractual Maturity Date) (Details) - USD ($) $ in Millions | Jun. 30, 2020 | Dec. 31, 2019
--- | --- | ---
Schedule of Investments [Line Items] |  |
Total available-for-sale debt securities | $ 29,225 | $ 30,284
Cash equivalents | 3,200 | 73
Held-to-maturity securities |  |
Schedule of Investments [Line Items] |  |
Debt securities, held-to-maturity, amortized cost, before other-than-temporary impairment | $ 1,390 | $ 1,568
Debt securities, held-to-maturity, yield | 3.20% | 3.20%
Debt securities, held-to-maturity, maturity, within one year, amortized Cost | $ 0 | $ 0
Debt securities, held-to-maturity, due in one year or less, yield | 0.00% | 0.00%
Debt securities, held-to-maturity, maturity, one through five years, amortized Cost | $ 14 | $ 21
Debt securities, held-to-maturity, due after one year through five years, yield | 2.40% | 2.20%
Debt securities, held-to-maturity, maturity, after five through ten years, amortized cost | $ 0 | $ 0
Debt securities, held-to-maturity, due after five years through ten years, yield | 0.00% | 0.00%
Debt securities, held-to-maturity, maturity, after 10 Years, amortized cost | $ 1,376 | $ 1,547
Debt securities, held-to-maturity, due after ten years, yield | 3.20% | 3.20%
Available-for-sale securities | US Treasury |  |
Schedule of Investments [Line Items] |  |
Total available-for-sale debt securities | $ 807 | $ 2,048
Debt securities, available-for-sale, yield | 1.20% | 1.50%
Debt securities, available-for-sale, due in one year or less | $ 14 | $ 65
Debt securities, available-for-sale, due in one year or less, yield | 0.30% | 2.10%
Debt securities, available-for-sale, due after one year through five years | $ 709 | $ 1,590
Debt securities, available-for-sale, due after one year through five years, yield | 1.10% | 1.40%
Debt securities, available-for-sale, due after five years through ten years | $ 84 | $ 393
Debt securities, available-for-sale, due after five years through ten years, yield | 1.70% | 1.70%
Debt securities, available-for-sale, due after ten years | $ 0 | $ 0
Debt securities, available-for-sale, due after ten years, yield | 0.00% | 0.00%
Debt securities, available-for-sale, amortized cost | $ 784 | $ 2,059
Available-for-sale securities | US States and political subdivisions |  |
Schedule of Investments [Line Items] |  |
Total available-for-sale debt securities | $ 913 | $ 641
Debt securities, available-for-sale, yield | 3.20% | 3.10%
Debt securities, available-for-sale, due in one year or less | $ 20 | $ 22
Debt securities, available-for-sale, due in one year or less, yield | 2.50% | 2.70%
Debt securities, available-for-sale, due after one year through five years | $ 88 | $ 75
Debt securities, available-for-sale, due after one year through five years, yield | 2.40% | 2.30%
Debt securities, available-for-sale, due after five years through ten years | $ 176 | $ 159
Debt securities, available-for-sale, due after five years through ten years, yield | 2.90% | 2.80%
Debt securities, available-for-sale, due after ten years | $ 629 | $ 385
Debt securities, available-for-sale, due after ten years, yield | 3.40% | 3.40%
Debt securities, available-for-sale, amortized cost | $ 876 | $ 623
Available-for-sale securities | Foreign government |  |
Schedule of Investments [Line Items] |  |
Total available-for-sale debt securities | $ 162 | $ 186
Debt securities, available-for-sale, yield | 2.10% | 1.90%
Debt securities, available-for-sale, due in one year or less | $ 8 | $ 35
Debt securities, available-for-sale, due in one year or less, yield | 1.70% | 0.40%
Debt securities, available-for-sale, due after one year through five years | $ 79 | $ 65
Debt securities, available-for-sale, due after one year through five years, yield | 2.30% | 2.30%
Debt securities, available-for-sale, due after five years through ten years | $ 75 | $ 86
Debt securities, available-for-sale, due after five years through ten years, yield | 2.00% | 2.30%
Debt securities, available-for-sale, due after ten years | $ 0 | $ 0
Debt securities, available-for-sale, due after ten years, yield | 0.00% | 0.00%
Debt securities, available-for-sale, amortized cost | $ 153 | $ 184
Available-for-sale securities | Agency mortgage-backed residential |  |
Schedule of Investments [Line Items] |  |
Total available-for-sale debt securities | $ 19,884 | $ 21,404
Debt securities, available-for-sale, yield | 3.20% | 3.20%
Debt securities, available-for-sale, due in one year or less | $ 0 | $ 0
Debt securities, available-for-sale, due in one year or less, yield | 0.00% | 0.00%
Debt securities, available-for-sale, due after one year through five years | $ 0 | $ 0
Debt securities, available-for-sale, due after one year through five years, yield | 0.00% | 0.00%
Debt securities, available-for-sale, due after five years through ten years | $ 44 | $ 47
Debt securities, available-for-sale, due after five years through ten years, yield | 2.00% | 2.00%
Debt securities, available-for-sale, due after ten years | $ 19,840 | $ 21,357
Debt securities, available-for-sale, due after ten years, yield | 3.20% | 3.20%
Debt securities, available-for-sale, amortized cost | $ 19,136 | $ 21,183
Available-for-sale securities | Mortgage-backed residential |  |
Schedule of Investments [Line Items] |  |
Total available-for-sale debt securities | $ 3,425 | $ 2,850
Debt securities, available-for-sale, yield | 3.20% | 3.20%
Debt securities, available-for-sale, due in one year or less | $ 0 | $ 0
Debt securities, available-for-sale, due in one year or less, yield | 0.00% | 0.00%
Debt securities, available-for-sale, due after one year through five years | $ 0 | $ 0
Debt securities, available-for-sale, due after one year through five years, yield | 0.00% | 0.00%
Debt securities, available-for-sale, due after five years through ten years | $ 0 | $ 0
Debt securities, available-for-sale, due after five years through ten years, yield | 0.00% | 0.00%
Debt securities, available-for-sale, due after ten years | $ 3,425 | $ 2,850
Debt securities, available-for-sale, due after ten years, yield | 3.20% | 3.20%
Debt securities, available-for-sale, amortized cost | $ 3,387 | $ 2,841
Available-for-sale securities | Agency mortgage-backed commercial |  |
Schedule of Investments [Line Items] |  |
Total available-for-sale debt securities | $ 1,786 | $ 1,382
Debt securities, available-for-sale, yield | 2.50% | 2.90%
Debt securities, available-for-sale, due in one year or less | $ 0 | $ 0
Debt securities, available-for-sale, due in one year or less, yield | 0.00% | 0.00%
Debt securities, available-for-sale, due after one year through five years | $ 3 | $ 3
Debt securities, available-for-sale, due after one year through five years, yield | 3.30% | 3.20%
Debt securities, available-for-sale, due after five years through ten years | $ 1,247 | $ 1,109
Debt securities, available-for-sale, due after five years through ten years, yield | 2.60% | 3.00%
Debt securities, available-for-sale, due after ten years | $ 536 | $ 270
Debt securities, available-for-sale, due after ten years, yield | 2.20% | 2.40%
Debt securities, available-for-sale, amortized cost | $ 1,647 | $ 1,344
Available-for-sale securities | Mortgage-backed commercial |  |
Schedule of Investments [Line Items] |  |
Total available-for-sale debt securities | $ 38 | $ 42
Debt securities, available-for-sale, yield | 3.60% | 3.50%
Debt securities, available-for-sale, due in one year or less | $ 0 | $ 0
Debt securities, available-for-sale, due in one year or less, yield | 0.00% | 0.00%
Debt securities, available-for-sale, due after one year through five years | $ 0 | $ 0
Debt securities, available-for-sale, due after one year through five years, yield | 0.00% | 0.00%
Debt securities, available-for-sale, due after five years through ten years | $ 0 | $ 0
Debt securities, available-for-sale, due after five years through ten years, yield | 0.00% | 0.00%
Debt securities, available-for-sale, due after ten years | $ 38 | $ 42
Debt securities, available-for-sale, due after ten years, yield | 3.60% | 3.50%
Debt securities, available-for-sale, amortized cost | $ 41 | $ 41
Available-for-sale securities | Asset-backed |  |
Schedule of Investments [Line Items] |  |
Total available-for-sale debt securities | $ 356 | $ 368
Debt securities, available-for-sale, yield | 3.40% | 3.50%
Debt securities, available-for-sale, due in one year or less | $ 0 | $ 0
Debt securities, available-for-sale, due in one year or less, yield | 0.00% | 0.00%
Debt securities, available-for-sale, due after one year through five years | $ 294 | $ 317
Debt securities, available-for-sale, due after one year through five years, yield | 3.50% | 3.60%
Debt securities, available-for-sale, due after five years through ten years | $ 28 | $ 5
Debt securities, available-for-sale, due after five years through ten years, yield | 2.60% | 2.70%
Debt securities, available-for-sale, due after ten years | $ 34 | $ 46
Debt securities, available-for-sale, due after ten years, yield | 3.10% | 3.00%
Debt securities, available-for-sale, amortized cost | $ 352 | $ 365
Available-for-sale securities | Corporate debt |  |
Schedule of Investments [Line Items] |  |
Total available-for-sale debt securities | $ 1,854 | $ 1,363
Debt securities, available-for-sale, yield | 3.00% | 3.20%
Debt securities, available-for-sale, due in one year or less | $ 153 | $ 125
Debt securities, available-for-sale, due in one year or less, yield | 2.90% | 2.90%
Debt securities, available-for-sale, due after one year through five years | $ 705 | $ 580
Debt securities, available-for-sale, due after one year through five years, yield | 2.90% | 3.00%
Debt securities, available-for-sale, due after five years through ten years | $ 973 | $ 649
Debt securities, available-for-sale, due after five years through ten years, yield | 3.10% | 3.40%
Debt securities, available-for-sale, due after ten years | $ 23 | $ 9
Debt securities, available-for-sale, due after ten years, yield | 2.40% | 3.30%
Debt securities, available-for-sale, amortized cost | $ 1,761 | $ 1,327
Available-for-sale securities | Available-for-sale debt securities |  |
Schedule of Investments [Line Items] |  |
Total available-for-sale debt securities | $ 29,225 | $ 30,284
Debt securities, available-for-sale, yield | 3.10% | 3.10%
Debt securities, available-for-sale, due in one year or less | $ 195 | $ 247
Debt securities, available-for-sale, due in one year or less, yield | 2.60% | 2.30%
Debt securities, available-for-sale, due after one year through five years | $ 1,878 | $ 2,630
Debt securities, available-for-sale, due after one year through five years, yield | 2.30% | 2.10%
Debt securities, available-for-sale, due after five years through ten years | $ 2,627 | $ 2,448
Debt securities, available-for-sale, due after five years through ten years, yield | 2.80% | 2.80%
Debt securities, available-for-sale, due after ten years | $ 24,525 | $ 24,959
Debt securities, available-for-sale, due after ten years, yield | 3.20% | 3.20%
Debt securities, available-for-sale, amortized cost | $ 28,137 | $ 29,967
Debt securities, available-for-sale, maturity, within one year, amortized cost | 193 | 246
Debt securities, available-for-sale, maturity, after one through five years, amortized cost | 1,821 | 2,624
Debt securities, available-for-sale, maturity, after five through ten years, amortized cost | 2,431 | 2,378
Debt securities, available-for-sale, maturity, after ten years, amortized cost | 23,692 | 24,719
Held-to-maturity securities | Agency mortgage-backed residential |  |
Schedule of Investments [Line Items] |  |
Debt securities, held-to-maturity, amortized cost, before other-than-temporary impairment | $ 1,376 | $ 1,547
Debt securities, held-to-maturity, yield | 3.20% | 3.20%
Debt securities, held-to-maturity, maturity, within one year, amortized Cost | $ 0 | $ 0
Debt securities, held-to-maturity, due in one year or less, yield | 0.00% | 0.00%
Debt securities, held-to-maturity, maturity, one through five years, amortized Cost | $ 0 | $ 0
Debt securities, held-to-maturity, due after one year through five years, yield | 0.00% | 0.00%
Debt securities, held-to-maturity, maturity, after five through ten years, amortized cost | $ 0 | $ 0
Debt securities, held-to-maturity, due after five years through ten years, yield | 0.00% | 0.00%
Debt securities, held-to-maturity, maturity, after 10 Years, amortized cost | $ 1,376 | $ 1,547
Debt securities, held-to-maturity, due after ten years, yield | 3.20% | 3.20%
Held-to-maturity securities | Asset-backed |  |
Schedule of Investments [Line Items] |  |
Debt securities, held-to-maturity, amortized cost, before other-than-temporary impairment | $ 14 | $ 21
Debt securities, held-to-maturity, yield | 2.40% | 2.20%
Debt securities, held-to-maturity, maturity, within one year, amortized Cost | $ 0 | $ 0
Debt securities, held-to-maturity, due in one year or less, yield | 0.00% | 0.00%
Debt securities, held-to-maturity, maturity, one through five years, amortized Cost | $ 14 | $ 21
Debt securities, held-to-maturity, due after one year through five years, yield | 2.40% | 2.20%
Debt securities, held-to-maturity, maturity, after five through ten years, amortized cost | $ 0 | $ 0
Debt securities, held-to-maturity, due after five years through ten years, yield | 0.00% | 0.00%
Debt securities, held-to-maturity, maturity, after 10 Years, amortized cost | $ 0 | $ 0
Debt securities, held-to-maturity, due after ten years, yield | 0.00% | 0.00%

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