LEASES (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Jan. 01, 2019
Operating Lease, Cost	$ 494	$ 484	$ 532
Amortization of right-of-use assets - finance	76	58	39
Interest on lease liabilities - finance	27	25	25
Total finance lease cost	103	83	64
Short-term lease cost	238	213	204
Variable lease cost	381	199	198
Sublease income	(6)	(5)	(4)
Total lease cost	1,210	974	994
Operating cash flows for operating leases	497	482	544
Operating cash flows for finance leases	27	25	25
Financing cash flows for finance leases	74	58	34
Right-of-Use Asset Obtained in Exchange for Operating Lease Liability	25	185	2,476
Right-of-Use Asset Obtained in Exchange for Finance Lease Liability	512	178	89
Operating lease right-of-use assets	1,412	1,856
Total Lease Assets	2,202	2,305
Operating lease liabilities - current	314	416
Operating lease liabilities - noncurrent	1,149	1,521
Total Lease Liabilities	2,332	2,455
Payments to Acquire Equipment on Lease	$ 694	$ 5	9
Weighted-average remaining lease term - Operating leases	7 years 10 months 24 days	7 years 7 months 6 days
Weighted-average remaining lease term - Finance leases	11 years 9 months 18 days	11 years 7 months 6 days
Weighted-average discount rate - Operating leases	3.72%	3.84%
Weighted-average discount rate - Finance leases	4.17%	5.41%
Lessee, Operating Lease, Liability, to be Paid, Year One	$ 346
Finance Lease, Liability, to be Paid, Year One	137
Lessee, Operating Lease, Liability, to be Paid, Year Two	281
Finance Lease, Liability, Payments, Due Year Two	162
Lessee, Operating Lease, Liability, Payments, Due Year Three	218
Finance Lease, Liability, Payments, Due Year Three	103
Lessee, Operating Lease, Liability, Payments, Due Year Four	181
Finance Lease, Liability, Payments, Due Year Four	74
Lessee, Operating Lease, Liability, Payments, Due Year Five	145
Finance Lease, Liability, Payments, Due Year Five	69
Lessee, Operating Lease, Liability, Payments, Due after Year Five	570
Finance Lease, Liability, Payments, Due after Year Five	551
Lessee, Operating Lease, Liability, Payments, Due	1,741
Finance Lease, Liability, Payment, Due	1,096
Lessee, Operating Lease, Liability, Undiscounted Excess Amount	278
Finance Lease, Liability, Undiscounted Excess Amount	227
Lease liability	1,463
Finance Lease, Liability	869
Lessee, Additional Leases Not yet Commenced, Assumptions and Judgment, Amount	$ 113
Lessee, Additional Leases Not yet Commenced, Term of Contract	16 years
Lease Buy-Outs
Payments to Acquire Equipment on Lease	$ 687
Increase (Decrease) Operating Lease, Right-of-Use Asset	(166)
Increase (Decrease) Operating Lease, Liability, Current	(44)
Increase (Decrease) Operating Lease, Liability, Noncurrent	(158)
Gain (Loss) on Termination of Lease	(37)
Lease Contract Amendments
Increase (Decrease) Right-of-Use Asset Obtained in Exchange for Operating Lease Liability	(193)
Increase (Decrease) Operating Lease, Liability, Current	(34)
Increase (Decrease) Operating Lease, Liability, Noncurrent	(73)
Increase (Decrease) Finance Lease, Liability, Noncurrent	152
Increase (Decrease) Finance Lease, Liability, Current	(2)
Property, Plant and Equipment
Finance Lease, Right-of-Use Asset, before Accumulated Amortization	1,158	$ 665
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment
Finance Lease, Right-of-Use Asset, Accumulated Amortization	368	216
Long-term Debt Due Within One Year
Finance Lease, Liability	106	54
Long-Term Debt and Lease Obligations
Finance Lease, Liability	763	464
Residual Value Guarantees
Recorded liability	0	22
Maximum future payments	$ 280	$ 818
Accounting Standards Update 2016-02
Right-of-Use Asset Obtained in Exchange for Operating Lease Liability			$ 2,300
Operating lease right-of-use assets				$ 2,300
Maximum
Lessee, Operating and Finance Leases, Remaining Lease Term	54 years