Asset Impairments	9 Months Ended
Sep. 30, 2020
Goodwill and Intangible Assets Disclosure [Abstract]
Asset Impairments	Asset ImpairmentsThe Company recorded an impairment loss of $19 million related to a facility in the Thermal segment during the second quarter of 2019. The fair value of the facility was determined using an income approach by applying a discounted cash flow methodology to the long-term budgets for each respective plant. The income approach utilized estimates of discounted future cash flows, which were Level 3 fair value measurement and include key inputs, such as forecasted power prices, operations and maintenance expense, and discount rates. The Company measured the impairment loss as the difference between the carrying amount and the fair value of the assets.

The entire disclosure for the details of the charge against earnings resulting from the aggregate write down of all assets from their carrying value to their fair value. Disclosure may also include a description of the impaired asset and facts and circumstances leading to the impairment, amount of the impairment loss and where the loss is located in the income statement, method(s) for determining fair value, and the segment in which the impaired asset is reported.

No definition available.

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