Equipment, Property and Improvements - Composition of Partnership's Equipment, Property and Improvements (Detail) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Equipment, property and improvements, at cost	$ 1,856	$ 1,768
Less: accumulated depreciation and amortization	1,236	1,152
Equipment, property and improvements, net	620	616
Buildings and Improvements [Member]
Property, Plant and Equipment [Line Items]
Equipment, property and improvements, at cost	1,050	1,012
Equipment, Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Equipment, property and improvements, at cost	763	713
Land [Member]
Property, Plant and Equipment [Line Items]
Equipment, property and improvements, at cost	$ 43	$ 43

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 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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