Equity Equity, Net Earnings (Details) - USD ($) $ in Millions |
9 Months Ended | ||||||
|---|---|---|---|---|---|---|---|
Sep. 30, 2017 |
Sep. 30, 2016 |
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| Schedule of Capitalization, Equity [Line Items] | |||||||
| Net Income (Loss) Attributable To Partners | [1] | $ 299 | $ 263 | ||||
| General Partner | |||||||
| Schedule of Capitalization, Equity [Line Items] | |||||||
| Participating Securities, Distributed and Undistributed Earnings (Loss), Basic | 94 | 89 | |||||
| Income (Loss) of General Partner Unit Issuance and Incentive Distribution Rights | [2] | 40 | 0 | ||||
| Net Income (Loss) Attributable To Partners | 119 | 89 | |||||
| Common | |||||||
| Schedule of Capitalization, Equity [Line Items] | |||||||
| Participating Securities, Distributed and Undistributed Earnings (Loss), Basic | 220 | 153 | |||||
| Income (Loss) of General Partner Unit Issuance and Incentive Distribution Rights | [2] | (40) | 0 | ||||
| Net Income (Loss) Attributable To Partners | 180 | $ 153 | |||||
| IDR/GP Transaction | General Partner | |||||||
| Schedule of Capitalization, Equity [Line Items] | |||||||
| Net Income (Loss) Attributable To Partners | $ 134 | ||||||
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