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Equity (Details) - USD ($) $ in Millions | 1 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2016 | Sep. 30, 2016 | Sep. 30, 2015
Class of Stock [Line Items] |  |  |
Conversion of common units to common shares (in units/ shares) |  | 87,000 | 160,160
Common Stock Issued to Public Under At-the-Market Program |  |  |
Class of Stock [Line Items] |  |  |
At-market-stock aggregate gross sales price | $ 200.0 |  |

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