VARIABLE INTEREST ENTITIES (Tables)  | 
6 Months Ended | ||||||||||||||||||||||||||||||||||||||||
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Jun. 30, 2020  | |||||||||||||||||||||||||||||||||||||||||
| Organization, Consolidation and Presentation of Financial Statements [Abstract] | |||||||||||||||||||||||||||||||||||||||||
| Schedule of Variable Interest Entities [Table Text Block] | The consolidated balance sheet as of June 30, 2020 includes the following amounts for SunCoke Middletown:
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- References No definition available. 
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- Definition The entire disclosure for supplemental balance sheet disclosures, including descriptions and amounts for assets, liabilities, and equity. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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