Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1(e))
-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Related Parties
-URI http://asc.fasb.org/extlink&oid=16382449

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-07.1(c))
-URI http://asc.fasb.org/extlink&oid=6488393&loc=d3e606610-122999

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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Summary of Significant Accounting Policies - Schedule of Revenues (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Third parties									$ 201.5	$ 222.8	$ 155.0
Related parties									89.8	103.7	95.3
Total revenue	$ 75.6	$ 67.9	$ 71.1	$ 76.7	$ 84.6	$ 96.2	$ 79.8	$ 65.9	291.3	326.5	250.3
Storage Services
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Third parties									8.4	8.5	8.5
Related parties									8.6	7.5	9.2
Total revenue									17.0	16.0	17.7
Transportation and Allowance Oil
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Third parties									193.1	214.3	146.5
Related parties									81.2	96.2	86.1
Total revenue									$ 274.3	$ 310.5	$ 232.6