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Business and Basis of Presentation - Description of the Business (Details) - USD ($) $ in Billions | Nov. 05, 2015 | Apr. 01, 2011
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Predecessor |  |
Business Acquisition [Line Items] |  |
Credit bid to acquire business | $ 1.1 |
Walter Energy, Inc. | Senior Secured Notes | Senior Secured Notes due 2019 |  |
Business Acquisition [Line Items] |  |
Stated interest rate |  | 9.50%

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- Definition Contractual interest rate for funds borrowed, under the debt agreement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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