SUBSEQUENT EVENTS (Details) - Subsequent event	Apr. 15, 2020 employee
Gibson County mining complex
Subsequent Event
Number of employees terminated	116
Hamilton mining complex
Subsequent Event
Number of employees terminated	78

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

No definition available.

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