Acquisitions, Dispositions, and Impairment of Long-Lived Assets Acquisitions, Dispositions, and Impairments of Long-Lived Assets (Tables)

12 Months Ended

Dec. 31, 2017

Business Combinations [Abstract]

Significant Unobservable Inputs [Table Text Block]

The following table sets forth a description of significant unobservable inputs used in the valuation of the FitzPatrick, Pilgrim, Palisades, and Indian Point plants and related assets:

Significant Unobservable Inputs	Amount	Weighted-Average
2015
Weighted-average cost of capital
FitzPatrick	7.5%	7.5%
Pilgrim (a)	7.5%-8.0%	7.9%
Palisades	7.5%	7.5%
Long-term pre-tax operating margin (cash basis)
FitzPatrick	10.2%	10.2%
Pilgrim (a)	2.4%-10.6%	8.1%
Palisades (b)	30.8%	30.8%
2016
Weighted-average cost of capital
Indian Point (c)	7.0%-7.5%	7.2%
Palisades	6.5%	6.5%
Long-term pre-tax operating margin (cash basis)
Indian Point	19.7%	19.7%
Palisades (b) (d)	17.8%-38.8%	34.6%

(a) The fair value of Pilgrim was based on the probability weighting of two potential scenarios.

(b) Most of the Palisades output is sold under a 15-year power purchase agreement, entered at the plant’s acquisition in 2007, that is scheduled to expire in 2022. The power purchase agreement prices currently exceed market prices and escalate each year, up to $61.50/MWh in 2022.

(c) The cash flows extending through the 2021 shutdown at Indian Point 3 were assigned a higher discount factor to incorporate the increased risk associated with longer operations.

(d) The fair value of Palisades at December 31, 2016 is based on the probability weighting of whether the PPA will terminate before the originally scheduled termination in 2022.