Inventories (Composition of Inventory) (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Finished goods inventory at average cost:
Finished goods inventory at average cost	$ 878	$ 891
Less: Excess of average cost over LIFO cost (LIFO reserve)	(152)	(155)
Less: Other inventory reserves	(35)	(35)
Inventories, net	691	701
Valves, Automation, Measurement And Instrumentation [Member]
Finished goods inventory at average cost:
Finished goods inventory at average cost	355	355
Carbon Pipe, Fittings And Flanges [Member]
Finished goods inventory at average cost:
Finished goods inventory at average cost	246	268
All Other Products [Member]
Finished goods inventory at average cost:
Finished goods inventory at average cost	$ 277	$ 268

Amount before valuation and LIFO reserves of completed merchandise or goods expected to be sold within one year or operating cycle, if longer.

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Amount by which inventory stated at last-in first-out (LIFO) is less than (in excess of) inventory stated at other inventory cost methods.

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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Amount of valuation reserve for inventory.

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