Supplemental Balance Sheet Data - Inventory (Details) - USD ($) $ in Millions	Sep. 30, 2017	Dec. 31, 2016
Raw materials	$ 337	$ 329
Work in process	203	203
Finished goods	1,083	1,030
Supplies and other	298	280
Inventory, Gross	1,921	1,842
Excess of FIFO or weighted-average cost over LIFO cost	(173)	(163)
Total	1,748	1,679
LIFO
Raw materials	88	93
Work in process	106	114
Finished goods	396	430
Supplies and other	0	0
Inventory, Gross	590	637
Excess of FIFO or weighted-average cost over LIFO cost	(173)	(163)
Total	417	474
Non-LIFO
Raw materials	249	236
Work in process	97	89
Finished goods	687	600
Supplies and other	298	280
Inventory, Gross	1,331	1,205
Excess of FIFO or weighted-average cost over LIFO cost	0	0
Total	$ 1,331	$ 1,205