Other Assets and Liabilites - Schedule of Right of Use Assets and Future Maturities of Lease Liabilities (Details) $ in Millions	Dec. 31, 2019 USD ($)
Right of Use Assets
Right-of-Use Asset, Operating Lease	$ 1,823
Right-of-Use Asset, Finance Lease	113
Operating Lease Liabilities, Payments Due
2020, Operating Leases	375
2021, Operating Leases	377
2022, Operating Leases	334
2023, Operating Lease	281
2024, Operating Leases	236
Thereafter, Operating Leases	763
Total lease payments, Operating Leases	2,366
Less: imputed interest, Operating Lease	245
Total lease liabilities, Operating Leases	$ 2,121
Weighted Average Remaining Lease Term, Operating Lease	7 years 8 months 12 days
Weighted Average Discount Rate, Percent, Operating Lease	2.60%
Finance Lease Liabilities, Payments, Due
2020, Finance Leases	$ 15
2021, Finance Leases	16
2022, Finance Leases	16
2023, Finance Lease	13
2024, Finance Leases	10
Thereafter, Finance Leases	76
Total lease payments, Finance Leases	146
Less: imputed interest, Finance Leases	23
Total lease liabilities, Finance Leases	$ 123
Weighted Average Remaining Lease Term, Finance Lease	11 years 4 months 24 days
Weighted Average Discount Rate, Percent, Finance Lease	3.40%