Leases - Classification of Finance Leases (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Finance Leases
Property, plant and equipment	$ 8,293	$ 7,778
Less: Accumulated depreciation and amortization	6,086	5,576
Property, plant and equipment, net	2,207	2,202
Current portion of long-term debt	8	19
Long-term debt, net	1,502	$ 1,605
Total finance lease liabilities	4
Finance leases
Finance Leases
Property, plant and equipment	7
Less: Accumulated depreciation and amortization	4
Property, plant and equipment, net	3
Current portion of long-term debt	1
Long-term debt, net	3
Total finance lease liabilities	$ 4

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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

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Amount of long-term debt and lease obligation, classified as noncurrent.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Finance Lease [Abstract]

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