v3.8.0.1

Related-Party Transactions Related-Party Transactions, Summary of Affiliate Transactions (Details) - USD ($) $ / shares in Units, $ in Millions |  |  | 3 Months Ended | 9 Months Ended
--- | --- | --- | --- | ---
Nov. 14, 2017 | Oct. 18, 2017 | Sep. 30, 2017 | Jun. 30, 2017 | Mar. 31, 2017 | Dec. 31, 2016 | Sep. 30, 2016 | Sep. 30, 2017 | Sep. 30, 2016
Cost of Reimbursable Expense |  |  | $ 7 |  |  |  |  | $ 3 | $ 12 | $ 12
Concentration Risk, Percentage |  |  | 49.00% |  |  |  |  | 60.00% | 49.00% |
Cash Dividends Paid to Parent Company |  |  |  |  |  |  |  |  | $ 223 |
Distribution Made to Limited Partner, Distributions Declared, Per Unit |  |  | $ 0.9852 | [1],[2] | $ 0.9710 | $ 0.9400 | $ 0.9100 |  |  |
Distribution Made to Limited Partner, Distribution Date |  |  | Nov. 14, 2017 |  | Aug. 14, 2017 | May 15, 2017 | Feb. 14, 2017 |  |  |
Subsequent Event |  |  |  |  |  |  |  |  |  |
Distribution Made to Limited Partner, Declaration Date |  | Oct. 18, 2017 |  |  |  |  |  |  |  |
Distribution Made to Limited Partner, Cash Distributions Paid | $ 125 |  |  |  |  |  |  |  |  |
[1] | (a)Represents cash distributions declared and paid during the nine months ended September 30, 2017, relating to the fourth quarter of 2016 through the second quarter of 2017.
[2] | (b)See reconciliation of general partner and limited partner’s earnings to amounts recorded to equity for the periods presented.

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