Note 3 - Inventories - Inventories (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Finished goods inventory at average cost	$ 675	$ 664
Less: Excess of average cost over LIFO cost (LIFO reserve)	(183)	(136)
Less: Other inventory reserves	(21)	(19)
Inventory, Net, Total	471	509
Valves, Automation, Measurement and Instrumentation [Member]
Finished goods inventory at average cost	242	279
Carbon Steel Pipe, Fittings and Flanges [Member]
Finished goods inventory at average cost	164	156
Gas Products [Member]
Finished goods inventory at average cost	161	126
All Other Products [Member]
Finished goods inventory at average cost	$ 108	$ 103

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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