Coal supply commitment

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- Definition

Priced coal supply commitment

+ References

No definition available.

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- Definition

Year Supply Commitments End

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No definition available.

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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- Definition

Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

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- Definition

Describes the periods of time over which an entity anticipates to receive utility from its property, plant and equipment (that is, the periods of time over which an entity allocates the initial cost of its property, plant and equipment).

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- Definition

Amount of each individual error being corrected in the correcting adjustment.

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Summary of Significant Accounting Policies (Narrative) (Details) $ in Thousands, T in Millions	12 Months Ended
	Dec. 31, 2015 T	Dec. 31, 2014	Dec. 31, 2013 USD ($)	Sep. 30, 2014
Revenue, Major Customer [Line Items]
Error correction amount \| $			$ 483
Sales Revenue, Goods, Net [Member]
Revenue, Major Customer [Line Items]
Percentage of total revenue from four largest customers	82.00%	71.00%	94.00%
Coal Supply Commitment [Member]
Revenue, Major Customer [Line Items]
Coal supply commitment	32
Year that supply commitments end	2024
Priced coal supply commitment	14
Savoy [Member]
Revenue, Major Customer [Line Items]
Equity method investment ownership percentage	40.00%			45.00%
Sunrise Energy [Member]
Revenue, Major Customer [Line Items]
Equity method investment ownership percentage	50.00%
Minimum [Member]
Revenue, Major Customer [Line Items]
Discount rate	5.50%
Estimated useful lives	P3Y
Maximum [Member]
Revenue, Major Customer [Line Items]
Discount rate	10.00%
Estimated useful lives	P25Y