Quarterly report pursuant to Section 13 or 15(d)

BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES - Cash Equivalents and Restricted Cash (Details)

v3.21.1
BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES - Cash Equivalents and Restricted Cash (Details)
$ in Millions
Mar. 31, 2021
USD ($)
Cripple Creek Project  
Basis Of Presentation [Line Items]  
Restricted cash account $ 180.0