Equity Method Investments and Related Party Transactions (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Equity Method Investments Disclosure [Abstract]
Proceeds from Equity Method Investment, Distribution	$ 270	$ 276	$ 192
Schedule of Equity Method Investments [Line Items]
Equity Method Investments	745	847
Equity Method Investment, Summarized Financial Information [Abstract]
Revenues and other income	1,269	1,294	770
Income from operations	588	631	346
Net income	459	508	313
Current assets	559	586
Noncurrent assets	931	1,044
Current liabilities	253	221
Noncurrent liabilities	87	94
Related Party Transactions [Abstract]
Revenue from Related Parties	48	60	54
Related Party Transaction, Purchases from Related Party	0	132	$ 103
Accounts Receivable, Related Parties, Current	25	24
Accounts Payable, Related Parties, Current	$ 15	14
EG Holdings [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage	60.00%
Equity Method Investments	$ 402	456
Alba Plant LLC [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage	52.00%
Equity Method Investments	$ 167	214
AMPCO [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage	45.00%
Equity Method Investments	$ 176	$ 177