Joint Venture with Peabody Energy	3 Months Ended
Mar. 31, 2021
Investment In Joint Venture [Abstract]
Joint Venture with Peabody Energy	3. Joint Venture with Peabody Energy The Company incurred expenses of $3.7 million for the three months ended March 31, 2020 associated with the regulatory approval process related to the proposed joint venture with Peabody that was terminated jointly by the parties due to the Federal Trade Commission blocking the joint venture during the third quarter of 2020. No amounts related to the joint venture were incurred for the three months ended March 31, 2021.

The entire disclosure for joint ventures. Joint ventures are entities owned and operated by a small group of businesses as a separate and specific business or project for the mutual benefit of the members of the group.

No definition available.

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