XML 30 R47.htm IDEA: XBRL DOCUMENT v3.20.1
Segment Information - Reconciliation of Revenue (Details) - USD ($)
$ in Thousands
3 Months Ended
Mar. 31, 2020
Mar. 31, 2019
Segment Reporting Information [Line Items]    
Total revenues $ 226,720 $ 378,290
Mining | Mining | Operating Segments    
Segment Reporting Information [Line Items]    
Total revenues 221,338 369,681
All other    
Segment Reporting Information [Line Items]    
Total revenues 5,382 $ 8,609
All other | Segment Reconciling Items    
Segment Reporting Information [Line Items]    
Total revenues $ 5,382