Lease Commitments - Schedule of Operating and Finance Lease Maturities (Details) $ in Millions	Jun. 30, 2020 USD ($)
Lessee, Operating Lease, Liability, Payment, Due [Abstract]
Remainder of 2020	$ 239
2021	406
2022	149
2023	109
2024	87
Thereafter	405
Total lease payments	1,395
Less: Interest	(235)
Total lease liabilities	1,160
Remainder of 2020
Remainder of 2020	17
2021	37
2022	34
2023	32
2024	30
Thereafter	261
Total lease payments	411
Less: Interest	(76)
Total lease liabilities	335
Operating and Finance Lease Liabilities, Payments, Due [Abstract]
Remainder of 2020	256
2021	443
2022	183
2023	141
2024	117
Thereafter	666
Total lease payments	1,806
Less: Interest	(311)
Total lease liabilities	$ 1,495
Weighted average lease term, operating lease	5 years 7 months 6 days
Weighted average discount rate, operating lease	5.03%
Weighted average lease term, finance lease	11 years 9 months 18 days
Weighted average discount rate, finance lease	3.36%

Finance Lease, Liability, to be Paid, after Year Four

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Present value of lessee's discounted obligation for lease payments from finance lease.

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Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid in remainder of current fiscal year.

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Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for finance lease.

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Weighted average remaining lease term for finance lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for operating lease having initial or remaining lease term in excess of one year to be paid in remainder of current fiscal year.

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Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for operating lease.

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Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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