Quarterly report pursuant to Section 13 or 15(d)

Debt (Details)

v3.22.1
Debt (Details) - USD ($)
shares in Millions, $ in Millions
3 Months Ended
May 12, 2021
Dec. 18, 2020
Aug. 12, 2020
Mar. 31, 2022
Dec. 31, 2021
2.75% Exchangeable Senior Debentures due 2050          
Debt disclosures          
Carrying value       $ 569 $ 585
Interest rate (as a percent)       2.75% 2.75%
1.25% Exchangeable Senior Debentures due 2050          
Debt disclosures          
Carrying value       $ 790 $ 818
Interest rate (as a percent)       1.25% 1.25%
1.75% Exchangeable Senior Debentures due 2046          
Debt disclosures          
Carrying value       $ 22 $ 25
Interest rate (as a percent)       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       $ 399 $ 399
SPV | Margin Loan Facility          
Debt disclosures          
Borrowings       300  
Carrying value       $ 1,600 $ 1,300
Number of business days prior to the maturity date       5 days  
Remaining borrowing capacity       $ 700  
SPV | Margin Loan Facility | Charter.          
Debt disclosures          
Number of common shares pledged as collateral       12.3  
Value of pledged collateral       $ 6,700  
SPV | Margin Loan Facility | Three-month LIBOR          
Debt disclosures          
Interest rate basis     three-month LIBOR    
Basis spread on variable rate 1.50% 1.85% 1.50%    
SPV | Term loan          
Debt disclosures          
Carrying value $ 1,150        
SPV | Revolving Credit Facility          
Debt disclosures          
Maximum borrowing capacity 1,150        
Amount outstanding 0        
SPV | Uncommitted Incremental Term Loan Facility          
Debt disclosures          
Maximum borrowing capacity $ 200