COMMITMENTS AND CONTINGENCIES - LESSOR INFORMATION (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018	[1]
Lessee, Lease, Description [Line Items]
Property, plant and equipment	$ 47,105		$ 46,615
Accumulated depreciation	(12,407)		(12,176)
Property, plant and equipment, net	34,698		$ 34,439
Lessor, Operating Lease, Payments, Fiscal Year Maturity [Abstract]
2019 (excluding first three months of 2019)	151
2020	200
2021	200
2022	200
2023	200
Thereafter	2,619
Total undiscounted cash flows	3,570
Minimum lease payments	50	$ 49
Variable lease payments	4	13
Total revenues from operating leases	54	62
Assets Leased to Others [Member]
Lessee, Lease, Description [Line Items]
Assets held for sale	148
Property, plant and equipment	1,026
Accumulated depreciation	(151)
Property, plant and equipment, net	875
Lessor, Operating Lease, Payments, Fiscal Year Maturity [Abstract]
Depreciation	$ 9	$ 17

[1] Derived from audited financial statements.