Accrued Liabilities - Third Parties - Schedule of Accrued Liabilities (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Payables and Accruals [Abstract]
Project accruals	$ 5	$ 7
Property taxes	5	4
Other accrued liabilities	2	2
Total accrued liabilities – third parties	$ 12	$ 13

Amount of expenses incurred but not yet paid classified as other, due within one year or the normal operating cycle, if longer.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.20)
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant