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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Amount of liabilities classified as other.

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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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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services 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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Property, plant and equipment and assets held for lease - Narrative (Detail) - Insurance and Other [Member] - USD ($) $ in Millions	Sep. 30, 2018	Jan. 01, 2018	Dec. 31, 2017
Property, Plant and Equipment [Line Items]
Property, plant and equipment, net	$ 24,357		$ 20,104
Property, plant and equipment, gross	44,872		37,424
Property, plant and equipment, accumulated depreciation	20,515		17,320
Machinery and equipment [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 28,594		$ 21,935
ASC 606 [Member] \| Aircraft Sold Under Fractional Aircraft Ownership Programs [Member]
Property, Plant and Equipment [Line Items]
Other liabilities		$ 3,500
ASC 606 [Member] \| Machinery and equipment [Member] \| Aircraft Sold Under Fractional Aircraft Ownership Programs [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, net		3,500
Property, plant and equipment, gross		5,300
Property, plant and equipment, accumulated depreciation		$ 1,800