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Financial Instruments and Other Guarantees - Narratives (Details)
$ in Millions
 3 Months Ended
Mar. 31, 2023
USD ($)
Mar. 31, 2022
USD ($)
Mar. 31, 2021
USD ($)
Apr. 14, 2023
USD ($)
Dec. 31, 2022
USD ($)
Nov. 06, 2020
USD ($)
Guarantee Obligations [Line Items]            
Line of Credit Facility, Current Borrowing Capacity $ 237.2          
Cumulative Collateral 557.8          
Net loss on early debt extinguishment 6.8 $ 23.5        
Interest expense 18.4 39.4        
Restricted Cash 814.2       $ 110.3  
Letter of Credit            
Guarantee Obligations [Line Items]            
Proceeds from Issuance of Debt     $ 324.0      
Line of Credit Facility, Increase (Decrease), Net $ (65.0)          
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage 6.00%          
Line of Credit Facility, Commitment Fee Percentage 0.50%          
Collateralized Letter of Credit Agreement            
Guarantee Obligations [Line Items]            
Letters of credit outstanding, amount $ 245.3          
Line of credit facility, maximum borrowing capacity $ 250.0          
Cash Collateral, Percentage of the aggregate amount of letters of credit outstanding 103.00%          
Cash-collateralized Letters of Credit $ 250.0          
Stated interest rate 0.75%          
Surety Trust Account            
Guarantee Obligations [Line Items]            
Restricted Cash $ 566.3       $ 0.0  
Accounts Receivable Securitization Program            
Guarantee Obligations [Line Items]            
Letters of credit outstanding, amount 101.3          
Line of Credit Facility, Previous Maximum Borrowing Capacity 175.0          
Line of credit facility, maximum borrowing capacity 225.0          
Accounts Receivable Securitization Program | Secured debt            
Guarantee Obligations [Line Items]            
Letters of credit outstanding, amount $ 190.7          
Basis spread on variable rate 2.10%          
LC Facility            
Guarantee Obligations [Line Items]            
Letters of credit outstanding, amount $ 223.8          
Maximum | Collateralized Letter of Credit Agreement            
Guarantee Obligations [Line Items]            
Transaction support agreements, additional collateral demands 5.0          
Subsequent Event | Accounts Receivable Securitization Program            
Guarantee Obligations [Line Items]            
Letters of credit outstanding, amount       $ 101.3    
Subsequent Event | Maximum            
Guarantee Obligations [Line Items]            
Debt Instrument, Collateral Amount       721.8    
Surety Bond            
Guarantee Obligations [Line Items]            
Debt Instrument, Transaction Support Agreements, Additional Collateral Posted 140.5          
Debt Instrument, Transaction Support Agreement, Additional Collateral Held $ 15.0          
Debt instrument, transaction support agreements, fair value of second liens on mining equipment           $ 200.0
Surety Bond | Subsequent Event            
Guarantee Obligations [Line Items]            
Surety Agreement Liquidity Covenant, Amount       $ 400.0    
Surety Bond | Subsequent Event | Maximum            
Guarantee Obligations [Line Items]            
Net Leverage Ratio       1.5    
Surety Bond | Subsequent Event | Minimum            
Guarantee Obligations [Line Items]            
Net Leverage Ratio       1.0    
Senior Notes | 3.250% Convertible Senior Notes due March 2028 (2028 Convertible Notes)            
Guarantee Obligations [Line Items]            
Stated interest rate 3.25%          
Senior Notes | Subsequent Event | 3.250% Convertible Senior Notes due March 2028 (2028 Convertible Notes)            
Guarantee Obligations [Line Items]            
Debt Instrument, Funded, Percent       50.00%    
Secured debt | Accounts Receivable Securitization Program            
Guarantee Obligations [Line Items]            
Outstanding borrowings $ 0.0          
Accounts Receivable from Securitization 15.3          
Interest expense $ 1.0 $ 0.9