Organization and Basis of Presentation (Consolidated Variable Interest Entities) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
ASSETS
Cash and cash equivalents	$ 56	$ 71
Restricted cash	5	5
Accounts receivable	1,683	1,789
Property, plant, and equipment, net	21,864	21,650
Goodwill	2,293	2,293
Intangible assets	846	849
Total Assets	36,434	36,288
Variable interest entity, primary beneficiary, restricted
ASSETS
Cash and cash equivalents	35	39
Restricted cash	5	5
Accounts receivable	38	46
Inventories	47	93
Property, plant, and equipment, net	436	441
Goodwill	25	25
Intangible assets	553	557
Other current and long-term assets	1	3
Total Assets	1,140	1,209
LIABILITIES
Accounts payable and accrued current liabilities	23	34
Other current and long-term liabilities	18	19
Total liabilities	41	53
SGG
ASSETS
Cash and cash equivalents	21	25
Restricted cash	0	0
Accounts receivable	10	9
Inventories	0	1
Property, plant, and equipment, net	394	395
Goodwill	25	25
Intangible assets	553	557
Other current and long-term assets	1	3
Total Assets	1,004	1,015
LIABILITIES
Accounts payable and accrued current liabilities	1	3
Other current and long-term liabilities	8	9
Total liabilities	$ 9	12
VIE ownership and non-ownership percentage	100.00%
VIE ownership percentage	55.00%
Other
ASSETS
Cash and cash equivalents	$ 14	14
Restricted cash	5	5
Accounts receivable	28	37
Inventories	47	92
Property, plant, and equipment, net	42	46
Goodwill	0	0
Intangible assets	0	0
Other current and long-term assets	0	0
Total Assets	136	194
LIABILITIES
Accounts payable and accrued current liabilities	22	31
Other current and long-term liabilities	10	10
Total liabilities	$ 32	$ 41