v3.20.2

Fair value of financial instruments - credit valuation (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Sep. 30, 2020 | Sep. 30, 2019 | Sep. 30, 2020 | Sep. 30, 2019 | Dec. 31, 2019
Asset acquisitions |  |  |  |  |
Gain in change in fair value of derivative instruments | $ 8.1 | $ 1.1 | $ 5.6 | $ (8.3) |
Recurring | Credit valuation adjustments |  |  |  |  |
Asset acquisitions |  |  |  |  |
Net increase in fair value |  |  | 0.5 |  | $ 1.1
Pre-tax gain in other comprehensive income |  |  | 0.1 |  | 0.1
Gain in change in fair value of derivative instruments |  |  | $ 0.4 |  | $ 1.0

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