Quarterly report pursuant to Section 13 or 15(d)

Debt (Details)

v3.21.2
Debt (Details) - USD ($)
$ in Thousands, shares in Millions
3 Months Ended 9 Months Ended
May 12, 2021
Dec. 18, 2020
Aug. 12, 2020
Sep. 30, 2021
Sep. 30, 2020
Sep. 30, 2021
Dec. 31, 2020
2.75% Exchangeable Senior Debentures due 2050              
Debt disclosures              
Carrying value       $ 607,976   $ 607,976 $ 608,804
Interest rate (as a percent)       2.75%   2.75% 2.75%
1.25% Exchangeable Senior Debentures due 2050              
Debt disclosures              
Carrying value       $ 840,378   $ 840,378 $ 836,971
Interest rate (as a percent)       1.25%   1.25% 1.25%
1.75% Exchangeable Senior Debentures due 2046              
Debt disclosures              
Carrying value       $ 30,105   $ 30,105 $ 26,350
Interest rate (as a percent)       1.75%   1.75% 1.75%
Exchange of debentures based on share price exceeds on par value       130.00%      
Minimum number of days share price exceeds par value       20 days      
Number of trading days       30 days      
Exchange period       1 year      
Line of credit              
Debt disclosures              
Carrying value       $ 426,000   $ 426,000 $ 704,000
SPV | Margin Loan Facility              
Debt disclosures              
Borrowings   $ 1,300,000   350,000 $ 125,000    
Carrying value       1,500,000   $ 1,500,000 $ 2,000,000
Number of business days prior to the maturity date 5 days         5 days  
Repayment of debt $ 850,000            
Remaining borrowing capacity       800,000   $ 800,000  
SPV | Margin Loan Facility | Charter.              
Debt disclosures              
Number of common shares pledged as collateral           12.3  
Value of pledged collateral       $ 8,900,000   $ 8,900,000  
SPV | Margin Loan Facility | Three-month LIBOR              
Debt disclosures              
Interest rate basis 3-month LIBOR   three-month LIBOR        
Basis spread on variable rate 1.50% 1.85% 1.50%        
SPV | Term loan              
Debt disclosures              
Carrying value $ 1,150,000            
SPV | Revolving Credit Facility              
Debt disclosures              
Maximum borrowing capacity 1,150,000            
Amount outstanding 0            
SPV | Uncommitted Incremental Term Loan Facility              
Debt disclosures              
Maximum borrowing capacity $ 200,000