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v3.20.2

Investment Securities - Additional Information (Details) - USD ($) $ in Millions |  |  | 3 Months Ended | 6 Months Ended |
--- | --- | --- | --- | --- | ---
Jun. 30, 2020 | Dec. 31, 2019 | Jun. 30, 2020 | Jun. 30, 2019 | Jun. 30, 2020 | Jun. 30, 2019 | Jan. 01, 2020
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |  |  |
Accrued interest receivable |  |  |  |  | $ 233 |  |
Proceeds from sales |  |  | $ 0 | $ 909 | 144 | $ 3,983 |
Debt Securities, Available-for-sale, Gain (Loss) |  |  |  | $ 15 | 1 | $ 39 |
Derivative, collateral, obligation to return securities | $ 1 | $ 1 | 1 |  | 1 |  |
Increase in retained earnings | 35,361 | 40,340 | 35,361 |  | 35,361 |  |
Decrease in AOCI | $ (3,981) | $ (1,156) | (3,981) |  | (3,981) |  |
Investment securities portfolio | US Treasury and Agency securities |  |  |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |  |  |
Percentage of portfolio | 97.00% | 96.00% |  |  |  |  |
Collateral pledged |  |  |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |  |  |
Debt securities, available-for-sale, restricted | $ 12,600 | $ 14,000 | $ 12,600 |  | $ 12,600 |  |
Cumulative effects from adoption of the CECL standard |  |  |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |  |  |
Increase in retained earnings |  |  |  |  |  |  | $ 11
Decrease in AOCI |  |  |  |  |  |  | $ 11

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- Definition Amount of interest income on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), from change in present value of expected cash flows, attributable to passage of time. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 45 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=121558606&loc=SL82922868-210454 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 50 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=121582814&loc=SL82922897-210455 + Details
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