XML 51 R39.htm IDEA: XBRL DOCUMENT v3.21.1
Goodwill and Other Intangible Assets (Quarterly Assessment for Indicators of Impairment) (Narrative) (Details)
3 Months Ended
Mar. 31, 2021
reportingunit
Oil and Gas [Member]  
Goodwill [Line Items]  
Number of reporting units 1