v3.8.0.1

Related-Party Transactions Related-Party Transactions, Summary of Affiliate Transactions (Details) - USD ($)
$ / shares in Units, $ in Millions

3 Months Ended

6 Months Ended

9 Months Ended

Nov. 14, 2017

Oct. 18, 2017

Sep. 30, 2017

^[1],[2]

Jun. 30, 2017

^[1]

Mar. 31, 2017

^[1]

Dec. 31, 2016

Jun. 30, 2016

Sep. 30, 2017

Sep. 30, 2016

Cost of Reimbursable Expense

$ 12

$ 12

Concentration Risk, Percentage

58.00%

44.00%

Cash Dividends Paid to Parent Company

$ 223

Distribution Made to Limited Partner, Distributions Declared, Per Unit

$ 0.9852

$ 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]	This distribution is net of $12.5 million waived by TLGP on either IDRs or common units for each of the three months ended September 30, 2017, June 30, 2017, and March 31, 2017.
[2]	This distribution was declared on October 18, 2017 and will be paid on the date of distribution.

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- Definition

This element represents disclosure of the total aggregate cash dividends paid to the entity by consolidated subsidiaries, by unconsolidated subsidiaries, and by 50% or less owned persons accounted for using the equity method.

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Cost associated with reimbursable income. This occurs when a services entity incurs expenses on behalf of the client and passes through the cost of reimbursable expenses to a client.

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