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Derivatives - Derivatives Associated with Fixed Income Trading Activities (Details) - USD ($) $ in Millions | Mar. 31, 2021 | Dec. 31, 2020
--- | --- | ---
Customer interest rate contracts |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Notional | $ 3,877 | $ 3,950
Assets | 111 | 207
Liabilities | 60 | 7
Offsetting upstream interest rate contracts |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Notional | 3,877 | 3,950
Assets | 6 | 2
Liabilities | 13 | 17
Option contracts purchased |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Notional | 3 |
Assets | 0 |
Liabilities | 0 |
Forwards and futures purchased |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Notional | 15,777 | 10,795
Assets | 12 | 62
Liabilities | 108 | 0
Forwards and futures sold |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Notional | 16,495 | 11,633
Assets | 119 | 1
Liabilities | $ 8 | $ 65

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- Definition Nominal or face amount used to calculate payment on derivative. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1B -URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5580258-113959 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5579245-113959 + Details
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