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Summary of Significant Accounting Policies - Additional Information (Detail) | 9 Months Ended
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Sep. 30, 2020 Country Segment Facility
Organization Consolidation And Presentation Of Financial Statements [Abstract] |
Number of reportable segments | Segment | 3
Number of commercial clean coal production facilities | Facility | 35
Number of countries in which the company has operations | 49
Number of countries in which the company does business through a network of correspondent brokers and consultants | 150

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- Definition Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 18 -URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8672-108599 + Details
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