v3.20.2

Segment and geographic information - risk (Details) - Revenues, net - Consolidated revenue | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2020 | Jun. 30, 2019 | Jun. 30, 2020 | Jun. 30, 2019
Georgia Power |  |  |  |
Consolidated revenue concentration |  |  |  |
Percentage of consolidated revenue | 11.40% | 11.10% |  | 10.10%
Niagara Mohawk |  |  |  |
Consolidated revenue concentration |  |  |  |
Percentage of consolidated revenue | 18.40% | 23.70% | 19.70% | 22.60%
Independent Electricity System Operator |  |  |  |
Consolidated revenue concentration |  |  |  |
Percentage of consolidated revenue | 13.20% | 11.30% | 14.00% | 12.50%
BC Hydro |  |  |  |
Consolidated revenue concentration |  |  |  |
Percentage of consolidated revenue |  | 10.80% | 11.90% | 10.10%
Equistar Chemicals, LP |  |  |  |
Consolidated revenue concentration |  |  |  |
Percentage of consolidated revenue | 11.30% | 11.00% | 10.80% | 12.20%

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