v3.7.0.1

Related-Party Transactions Related-Party Transactions, Summary of Affiliate Transactions (Details) - USD ($) $ / shares in Units, $ in Millions |  |  | 3 Months Ended | 6 Months Ended | 12 Months Ended
--- | --- | --- | --- | --- | ---
Aug. 14, 2017 | Jul. 19, 2017 | Jun. 30, 2017 | Mar. 31, 2017 | Jun. 30, 2016 | Jun. 30, 2017 | Jun. 30, 2016 | Dec. 31, 2016
Volume Gains (Losses) Value |  |  | $ 2.0 |  |  |  | $ 2.0 | $ 5.0 | $ 3.0 |  |
Distribution Made to Limited Partner, Distributions Declared, Per Unit |  |  | $ 0.971 | [1],[2] | $ 0.94 | [1] |  |  |  |  | $ 0.91
Distribution Made to Limited Partner, Distribution Date |  |  |  |  | May 15, 2017 |  |  |  |  |  | Feb. 14, 2017
Distribution Made to Limited Partner, Cash Distributions Paid |  |  |  |  |  |  |  | 195.0 | 149.0 | [3] |
Cost of Reimbursable Expense |  |  | $ 3.0 |  |  |  | 3.0 | 5.0 | 9.0 |  |
Cash Dividends Paid to Parent Company |  |  |  |  |  |  |  | (148.0) |  |  |
Subsequent Event |  |  |  |  |  |  |  |  |  |  |
Distribution Made to Limited Partner, Declaration Date |  | Jul. 19, 2017 |  |  |  |  |  |  |  |  |
Distribution Made to Limited Partner, Distribution Date | Aug. 14, 2017 |  |  |  |  |  |  |  |  |  |
Distribution Made to Limited Partner, Cash Distributions Paid | $ 75.0 |  |  |  |  |  |  |  |  |  |
North Dakota Gathering and Processing Assets [Member] |  |  |  |  |  |  |  |  |  |  |
managing member or general partner, subsequent distribution amount forfeited |  |  |  |  |  |  |  | 12.5 |  |  |
Secondment and Logistics Services Agreement | Andeavor to Partner |  |  |  |  |  |  |  |  |  |  |
Long-term Purchase Commitment, Amount |  |  | $ 5.0 |  |  |  | $ 1.0 | $ 10.0 | $ 6.0 |  |
[1] | This distribution is net of $12.5 million of IDRs waived by TLGP for each of the three months ended June 30, 2017 and March 31, 2017.
[2] | This distribution was declared on July 19, 2017 and will be paid on the date of distribution.
[3] | (a)Adjusted to include the historical results of the Predecessors. See Note 1 for further discussion.

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