Subsequent Events	9 Months Ended
Sep. 30, 2020
Subsequent Events [Abstract]
Subsequent Events	Subsequent EventsOn October 30, 2020, we reached an agreement with a subsidiary of Denbury Inc. to transfer to them the ownership of our remaining CO2 assets, including the NEJD and Free State pipelines. As a part of the agreement, we will receive total consideration of $92.5 million, of which $22.5 million was paid in the fourth quarter of 2020 upon execution of the agreement, and the remaining $70 million will be paid in equal installments in each quarter during 2021. We will record a loss of approximately $21.5 million in the fourth quarter which represents the difference between the proceeds and the net book value of the assets transferred.

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-URI http://asc.fasb.org/topic&trid=2122774

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6842918&loc=SL6314017-165662

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