v3.19.3.a.u2

Acquisitions and divestments - Koma Kulshan Associates (Details) $ in Millions |  |  | 12 Months Ended |  |
--- | --- | --- | --- | --- | ---
Jul. 27, 2018 USD ($) | Jun. 18, 2018 USD ($) item | Dec. 31, 2018 USD ($) | Dec. 31, 2019 USD ($) | Jun. 17, 2018
Asset acquisitions |  |  |  |  |
Percentage of equity method ownership interest |  | 100.00% |  |  |
Equity investments in unconsolidated affiliates |  |  | $ 140.8 | $ 96.6 |
Koma Kulshan Associates |  |  |  |  |
Asset acquisitions |  |  |  |  |
Percentage of equity method ownership interest |  | 50.00% |  |  | 49.75%
Equity investments in unconsolidated affiliates |  | $ 1.1 |  |  |
Number of owner parties with joint control | item |  | 2 |  |  |
Concrete |  |  |  |  |
Asset acquisitions |  |  |  |  |
Percentage of general partner interest purchased |  | 0.50% |  |  |
Purchase price of partnership interest |  | $ 1.1 |  |  |
Koma Kulshan Associates |  |  |  |  |
Asset acquisitions |  |  |  |  |
Purchase price | $ 12.5 |  |  |  |
Interest acquired in the plant | 100.00% |  |  |  |
Gain recognized from step acquisition |  |  | $ 7.2 |  |
Koma Kulshan Associates |  |  |  |  |
Asset acquisitions |  |  |  |  |
Percentage of general partner interest purchased | 50.00% |  |  |  |
Concrete | General Partner |  |  |  |  |
Asset acquisitions |  |  |  |  |
Percentage of equity method ownership interest |  |  |  |  | 0.50%
Concrete | Limited Partner |  |  |  |  |
Asset acquisitions |  |  |  |  |
Percentage of equity method ownership interest |  |  |  |  | 99.00%
Concrete | Koma Kulshan Associates |  |  |  |  |
Asset acquisitions |  |  |  |  |
Percentage of equity method ownership interest |  | 50.00% |  |  |
Covanta |  |  |  |  |
Asset acquisitions |  |  |  |  |
Percentage of equity method ownership interest | 50.00% |  |  |  |
Covanta | Koma Kulshan Associates |  |  |  |  |
Asset acquisitions |  |  |  |  |
Purchase price | $ 12.5 |  |  |  |

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