Asset Acquisitions, Dispositions and Other - Sale of Assets (Details) - USD ($) $ in Millions	1 Months Ended
Mar. 31, 2016	Jan. 31, 2016
Occidental Tower Building, Dallas Texas
Acquisitions, dispositions and other transactions
Proceeds from sale		$ 85
Piceance operations
Acquisitions, dispositions and other transactions
Proceeds from sale	$ 153
Gain (loss) on sale	$ 121

This item represents the amount of net sales proceeds received on disposal of an equity method investment.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 35
-Paragraph 35
-URI http://asc.fasb.org/extlink&oid=49116238&loc=d3e32847-111569

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Balance Type:	credit
Period Type:	duration