Annual report pursuant to Section 13 and 15(d)

Accumulated Other Comprehensive Income (Loss) - Change in Accumulated OCI (Details)

v3.20.4
Accumulated Other Comprehensive Income (Loss) - Change in Accumulated OCI (Details) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]      
Beginning balance $ 264,810 $ 265,325 $ 267,146
Adoption of accounting standard related to certain tax effects stranded in accumulated other comprehensive income (loss)     0
Cumulative adjustment for hedge accounting change 272,924 264,810 265,325
Net change 4,977 5,578 (3,916)
Ending balance 272,924 264,810 265,325
Cumulative Effect, Period of Adoption, Adjustment      
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]      
Beginning balance (2,406) 165  
Cumulative adjustment for hedge accounting change (2,406) (2,406) 165
Ending balance   (2,406) 165
Accumulated Other Comprehensive Income (Loss)      
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]      
Beginning balance (6,633) (12,211) (7,082)
Adoption of accounting standard related to certain tax effects stranded in accumulated other comprehensive income (loss)     (1,270)
Cumulative adjustment for hedge accounting change (1,656) (12,211) (12,211)
Ending balance (1,656) (6,633) (12,211)
Accumulated Other Comprehensive Income (Loss) | Cumulative Effect, Period of Adoption, Adjustment      
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]      
Beginning balance     57
Cumulative adjustment for hedge accounting change     57
Debt Securities      
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]      
Beginning balance 323 (5,552) (1,206)
Adoption of accounting standard related to certain tax effects stranded in accumulated other comprehensive income (loss)     (393)
Cumulative adjustment for hedge accounting change 5,122 323 (5,552)
Net change 4,799 5,875 (3,953)
Ending balance 5,122 323 (5,552)
Debt Securities | Cumulative Effect, Period of Adoption, Adjustment      
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]      
Beginning balance     0
Cumulative adjustment for hedge accounting change     0
Debit Valuation Adjustments      
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]      
Beginning balance (1,494) (531) (1,060)
Adoption of accounting standard related to certain tax effects stranded in accumulated other comprehensive income (loss)     (220)
Cumulative adjustment for hedge accounting change (1,992) (1,494) (531)
Net change (498) (963) 749
Ending balance (1,992) (1,494) (531)
Debit Valuation Adjustments | Cumulative Effect, Period of Adoption, Adjustment      
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]      
Beginning balance     0
Cumulative adjustment for hedge accounting change     0
Derivatives      
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]      
Beginning balance (400) (1,016) (831)
Adoption of accounting standard related to certain tax effects stranded in accumulated other comprehensive income (loss)     (189)
Cumulative adjustment for hedge accounting change 426 (400) (1,016)
Net change 826 616 (53)
Ending balance 426 (400) (1,016)
Derivatives | Cumulative Effect, Period of Adoption, Adjustment      
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]      
Beginning balance     57
Cumulative adjustment for hedge accounting change     57
Employee Benefit Plans      
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]      
Beginning balance (4,168) (4,304) (3,192)
Adoption of accounting standard related to certain tax effects stranded in accumulated other comprehensive income (loss)     (707)
Cumulative adjustment for hedge accounting change (4,266) (4,168) (4,304)
Net change (98) 136 (405)
Ending balance (4,266) (4,168) (4,304)
Employee Benefit Plans | Cumulative Effect, Period of Adoption, Adjustment      
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]      
Beginning balance     0
Cumulative adjustment for hedge accounting change     0
Foreign Currency      
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]      
Beginning balance (894) (808) (793)
Adoption of accounting standard related to certain tax effects stranded in accumulated other comprehensive income (loss)     239
Cumulative adjustment for hedge accounting change (946) (894) (808)
Net change (52) (86) (254)
Ending balance $ (946) $ (894) (808)
Foreign Currency | Cumulative Effect, Period of Adoption, Adjustment      
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]      
Beginning balance     0
Cumulative adjustment for hedge accounting change     $ 0