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Derivative Instruments and Hedging Activities - Net Gains (Losses) Recognized in Earnings Related to Derivatives in Fair Value Hedging and Cash Flow Hedging (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Interest and dividend income, securities | $ 2,411 | $ 2,211 | $ 1,711
Interest and fee income, loans | 25,862 | 24,728 | 23,388
Interest and dividend income, other | 240 | 237 | 123
Deposits | (3,420) | (2,598) | (1,602)
Securitized debt obligations | (523) | (496) | (327)
Senior and subordinated notes | (1,159) | (1,125) | (731)
Non-interest income | 718 | 1,002 | 542
Amortization of basis adjustment | 171 | 75 |
Non interest income - Other |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Realized gains on foreign exchange contracts reclassified from AOCI | 341 | 191 |
Fair value hedges | Interest income - Investment securities |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Net expense recognized on fair value hedges | (12) | (22) |
Fair value hedges | Interest income - Loans |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Net expense recognized on fair value hedges | 0 | 0 |
Fair value hedges | Interest income - Other |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Net expense recognized on fair value hedges | 0 | 0 |
Fair value hedges | Interest expense - Deposits |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Net expense recognized on fair value hedges | (103) | (84) |
Fair value hedges | Interest expense - Securitized Debt Obligation |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Net expense recognized on fair value hedges | (92) | (76) |
Fair value hedges | Interest expense - Senior and Subordinated Debt |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Net expense recognized on fair value hedges | (105) | (79) |
Fair value hedges | Non interest income - Other |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Net expense recognized on fair value hedges | 0 | 0 |
Fair value hedges | Interest rate contracts | Interest income - Investment securities |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Interest recognized on derivatives | (12) | (23) |
Gains (losses) recognized on derivatives | (278) | 34 |
Gains (losses) recognized on hedged items | 278 | (33) |
Excluded component of fair value hedges | 0 |  |
Fair value hedges | Interest rate contracts | Interest income - Loans |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Interest recognized on derivatives | 0 | 0 |
Gains (losses) recognized on derivatives | 0 | 0 |
Gains (losses) recognized on hedged items | 0 | 0 |
Excluded component of fair value hedges | 0 |  |
Fair value hedges | Interest rate contracts | Interest income - Other |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Interest recognized on derivatives | 0 | 0 |
Gains (losses) recognized on derivatives | 0 | 0 |
Gains (losses) recognized on hedged items | 0 | 0 |
Excluded component of fair value hedges | 0 |  |
Fair value hedges | Interest rate contracts | Interest expense - Deposits |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Interest recognized on derivatives | (108) | (76) |
Gains (losses) recognized on derivatives | 263 | (60) |
Gains (losses) recognized on hedged items | (258) | 52 |
Excluded component of fair value hedges | 0 |  |
Fair value hedges | Interest rate contracts | Interest expense - Securitized Debt Obligation |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Interest recognized on derivatives | (14) | (53) |
Gains (losses) recognized on derivatives | 45 | (61) |
Gains (losses) recognized on hedged items | (123) | 38 |
Excluded component of fair value hedges | 0 |  |
Fair value hedges | Interest rate contracts | Interest expense - Senior and Subordinated Debt |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Interest recognized on derivatives | (6) | 2 |
Gains (losses) recognized on derivatives | 704 | (212) |
Gains (losses) recognized on hedged items | (801) | 131 |
Excluded component of fair value hedges | (2) |  |
Fair value hedges | Interest rate contracts | Non interest income - Other |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Interest recognized on derivatives | 0 | 0 |
Gains (losses) recognized on derivatives | (9) | 0 |
Gains (losses) recognized on hedged items | 9 | 0 |
Excluded component of fair value hedges | 0 |  |
Cash flow hedges | Interest income - Investment securities |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Net income (expense) recognized on cash flow hedges | (8) | (9) |
Cash flow hedges | Interest income - Loans |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Net income (expense) recognized on cash flow hedges | (163) | (82) |
Cash flow hedges | Interest income - Other |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Net income (expense) recognized on cash flow hedges | 44 | 47 |
Cash flow hedges | Interest expense - Deposits |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Net income (expense) recognized on cash flow hedges | 0 | 0 |
Cash flow hedges | Interest expense - Securitized Debt Obligation |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Net income (expense) recognized on cash flow hedges | 0 | 0 |
Cash flow hedges | Interest expense - Senior and Subordinated Debt |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Net income (expense) recognized on cash flow hedges | 0 | 0 |
Cash flow hedges | Non interest income - Other |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Net income (expense) recognized on cash flow hedges | (1) | (2) |
Cash flow hedges | Interest rate contracts | Interest income - Investment securities |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Reclassification adjustment from AOCI on derivatives, net of tax | (8) | (9) |
Cash flow hedges | Interest rate contracts | Interest income - Loans |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Reclassification adjustment from AOCI on derivatives, net of tax | (163) | (82) |
Cash flow hedges | Interest rate contracts | Interest income - Other |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Reclassification adjustment from AOCI on derivatives, net of tax | 0 | 0 |
Cash flow hedges | Interest rate contracts | Interest expense - Deposits |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Reclassification adjustment from AOCI on derivatives, net of tax | 0 | 0 |
Cash flow hedges | Interest rate contracts | Interest expense - Securitized Debt Obligation |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Reclassification adjustment from AOCI on derivatives, net of tax | 0 | 0 |
Cash flow hedges | Interest rate contracts | Interest expense - Senior and Subordinated Debt |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Reclassification adjustment from AOCI on derivatives, net of tax | 0 | 0 |
Cash flow hedges | Interest rate contracts | Non interest income - Other |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Reclassification adjustment from AOCI on derivatives, net of tax | 0 | 0 |
Cash flow hedges | Foreign exchange contracts | Interest income - Investment securities |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Reclassification adjustment from AOCI on derivatives, net of tax | 0 | 0 |
Cash flow hedges | Foreign exchange contracts | Interest income - Loans |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Reclassification adjustment from AOCI on derivatives, net of tax | 0 | 0 |
Cash flow hedges | Foreign exchange contracts | Interest income - Other |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Reclassification adjustment from AOCI on derivatives, net of tax | 44 | 47 |
Cash flow hedges | Foreign exchange contracts | Interest expense - Deposits |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Reclassification adjustment from AOCI on derivatives, net of tax | 0 | 0 |
Cash flow hedges | Foreign exchange contracts | Interest expense - Securitized Debt Obligation |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Reclassification adjustment from AOCI on derivatives, net of tax | 0 | 0 |
Cash flow hedges | Foreign exchange contracts | Interest expense - Senior and Subordinated Debt |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Reclassification adjustment from AOCI on derivatives, net of tax | 0 | 0 |
Cash flow hedges | Foreign exchange contracts | Non interest income - Other |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Reclassification adjustment from AOCI on derivatives, net of tax | $ (1) | $ (2) |
Derivatives designated as accounting hedges |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Net derivative gains recognized in net income |  |  | 110
Derivatives designated as accounting hedges | Fair value hedges | Interest rate contracts | Non interest income - Other |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Gains (losses) recognized on derivatives |  |  | (212)
Gains (losses) recognized on hedged items |  |  | 216
Net fair value hedge ineffectiveness gains |  |  | 4
Derivatives designated as accounting hedges | Cash flow hedges | Non interest income - Other |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Reclassification adjustment from AOCI on derivatives, net of tax |  |  | 108
Derivatives designated as accounting hedges | Cash flow hedges | Interest rate contracts | Non interest income - Other |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Reclassification adjustment from AOCI on derivatives, net of tax |  |  | 91
Gains (losses) on derivatives not designated as accounting hedges |  |  | 2
Derivatives designated as accounting hedges | Cash flow hedges | Foreign exchange contracts | Non interest income - Other |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Gains (losses) on derivatives not designated as accounting hedges |  |  | $ 17

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