Basis of Presentation

9 Months Ended

Sep. 30, 2013

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block]

Basis of Presentation

The accompanying unaudited condensed consolidated financial statements include the accounts of Arch Coal, Inc. and its subsidiaries and controlled entities (the “Company”). The Company’s primary business is the production of thermal and metallurgical coal from surface and underground mines located throughout the United States, for sale to utility, industrial and steel producers both in the United States and around the world. The Company currently operates mining complexes in West Virginia, Kentucky, Maryland, Virginia, Illinois, Wyoming and Colorado. In addition, the Company is developing a metallurgical coal mine in West Virginia. All subsidiaries are wholly-owned. Intercompany transactions and accounts have been eliminated in consolidation.

The Company completed the sale of a subsidiary comprised of three mining complexes in the Western Bituminous reportable segment ("WBIT") on August 16, 2013. The results of these mining complexes have been segregated from continuing operations and are reflected, net of tax, as discontinued operations in the condensed consolidated statements of operations for all periods presented. See further discussion in Note 3, "Discontinued Operations".

In response to decreasing demand for thermal coal in Appalachia, the Company closed four mining complexes, temporarily idled a fifth complex, and curtailed production at other mines in the region in the second quarter of 2012. The operations continued to ship from inventory into the third quarter of 2012. The results for the closed and idled complexes are reflected in continuing operations in the condensed consolidating statements of operations for the three and nine month periods ended September 30, 2012. See further discussion in Note 5, "Impairment Charges".

The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States for interim financial reporting and U.S. Securities and Exchange Commission regulations. In the opinion of management, all adjustments, consisting of normal, recurring accruals considered necessary for a fair presentation, have been included. Results of operations for the three and nine month periods ended September 30, 2013 are not necessarily indicative of results to be expected for the year ending December 31, 2013. These financial statements should be read in conjunction with the audited financial statements and related notes as of and for the year ended December 31, 2012 included in the Company’s Annual Report on Form 10-K filed with the U.S. Securities and Exchange Commission.