Commitments, Contingencies and Guarantees (Maximum Potential Obligation) (Details) $ in Millions	Jun. 30, 2021 USD ($)
2034
Other Commitments [Line Items]
Guarantor Obligations, Maximum Exposure, Undiscounted	$ 1,243
2035
Other Commitments [Line Items]
Guarantor Obligations, Maximum Exposure, Undiscounted	2,444
2036
Other Commitments [Line Items]
Guarantor Obligations, Maximum Exposure, Undiscounted	3,599
2037
Other Commitments [Line Items]
Guarantor Obligations, Maximum Exposure, Undiscounted	2,850
2038
Other Commitments [Line Items]
Guarantor Obligations, Maximum Exposure, Undiscounted	2,300
2039
Other Commitments [Line Items]
Guarantor Obligations, Maximum Exposure, Undiscounted	11,350
2046
Other Commitments [Line Items]
Guarantor Obligations, Maximum Exposure, Undiscounted	$ 3,000