v3.7.0.1

Quarterly Financial Data (Unaudited) (Details) - USD ($) $ / shares in Units, $ 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
Quarterly Financial Data |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total revenues | $ 319 |  | $ 308 |  | $ 293 |  | $ 300 |  | $ 292 |  | $ 282 |  | $ 275 |  | $ 263 |  | $ 1,220 |  | $ 1,112 |  | $ 600
Operating expenses | 128 |  | 112 |  | 112 |  | 117 |  | 135 |  | 117 |  | 115 |  | 101 |  | 469 |  | 468 |  | 324
Operating income | 123 |  | 127 |  | 118 |  | 119 |  | 97 |  | 100 |  | 97 |  | 99 |  | 487 |  | 393 |  | 164
Net earnings (loss) | 73 |  | 81 |  | 76 |  | 85 |  | 59 |  | 65 |  | 60 |  | 65 |  | 315 |  | 249 |  | 56
Limited partners’ interest in net earnings | $ 32 |  | $ 48 |  | $ 47 |  | $ 60 |  | $ 46 |  | $ 54 |  | $ 49 |  | $ 50 |  | $ 187 |  | $ 199 |  | $ 56
Net earnings (loss) per limited partner unit: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common - basic (dollars per unit) | $ 0.31 | [1] | $ 0.46 | [1] | $ 0.48 | [1] | $ 0.64 | [1] | $ 0.49 | [1] | $ 0.62 | [1] | $ 0.60 | [1] | $ 0.63 | [1] | $ 1.87 | [1] | $ 2.33 | [1] | $ 0.96
Common - diluted (dollars per unit) | $ 0.31 | [1] | $ 0.46 | [1] | $ 0.48 | [1] | $ 0.64 | [1] | $ 0.49 | [1] | $ 0.62 | [1] | $ 0.60 | [1] | $ 0.63 | [1] | $ 1.87 | [1] | $ 2.33 | [1] | $ 0.96
[1] | The sum of four quarters may not equal annual results due to rounding or the quarterly number of units outstanding.

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