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Equity (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2018 | Jun. 30, 2017 | Jun. 30, 2018 | Jun. 30, 2017
Reconciliation of equity attributable to non-controlling interests |  |  |  |
NCI, beginning of period | $ (16.2) | $ (11.6) | $ (14.7) | $ (11.5)
Net income (loss) attributable to NCI, net of tax | 48.4 | 0.0 | 46.7 | (0.1)
Capital contribution by noncontrolling interest | 11.1 | 0.0 | 11.1 | 0.0
Distribution to noncontrolling interest | (50.0) | 0.0 | (50.0) | 0.0
Translation adjustment and other | (0.5) | 0.0 | (0.3) | 0.0
NCI, end of period | $ (7.2) | $ (11.6) | $ (7.2) | $ (11.6)

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