v3.26.1
LONG-TERM DEBT - Debt Activity (Details) - USD ($)
$ in Millions
 3 Months Ended 12 Months Ended
Mar. 31, 2026
Dec. 31, 2025
Long-Term Debt Repayments [Roll Forward]    
Total borrowings at face value, beginning balance $ 20,427  
Total repayments (6,670)  
Total borrowings at face value, ending balance 13,757 $ 20,427
Two-year term loan due 2026 (5.475% as of December 31, 2025) | Secured Debt    
Long-Term Debt Repayments [Roll Forward]    
Total borrowings at face value, beginning balance 1,280  
Total repayments (1,280)  
Total borrowings at face value, ending balance $ 0 $ 1,280
Debt term 2 years 2 years
Debt instrument interest rate stated percentage   5.475%
3.200% senior notes due 2026 | Senior Notes    
Long-Term Debt Repayments [Roll Forward]    
Total borrowings at face value, beginning balance $ 182  
Total repayments (182)  
Total borrowings at face value, ending balance $ 0 $ 182
Debt instrument interest rate stated percentage 3.20% 3.20%
7.500% debentures due 2026 | Debentures    
Long-Term Debt Repayments [Roll Forward]    
Total borrowings at face value, beginning balance $ 112  
Total repayments (112)  
Total borrowings at face value, ending balance $ 0 $ 112
Debt instrument interest rate stated percentage 7.50% 7.50%
3.000% senior notes due 2027 | Senior Notes    
Long-Term Debt Repayments [Roll Forward]    
Total borrowings at face value, beginning balance $ 216  
Total repayments (216)  
Total borrowings at face value, ending balance $ 0 $ 216
Debt instrument interest rate stated percentage 3.00% 3.00%
5.000% senior notes due 2027 | Senior Notes    
Long-Term Debt Repayments [Roll Forward]    
Total borrowings at face value, beginning balance $ 600  
Total repayments (600)  
Total borrowings at face value, ending balance $ 0 $ 600
Debt instrument interest rate stated percentage 5.00% 5.00%
7.125% debentures due 2027 | Debentures    
Long-Term Debt Repayments [Roll Forward]    
Total borrowings at face value, beginning balance $ 150  
Total repayments (150)  
Total borrowings at face value, ending balance $ 0 $ 150
Debt instrument interest rate stated percentage 7.125% 7.125%
8.500% senior notes due 2027 | Senior Notes    
Long-Term Debt Repayments [Roll Forward]    
Total borrowings at face value, beginning balance $ 489  
Total repayments (489)  
Total borrowings at face value, ending balance $ 0 $ 489
Debt instrument interest rate stated percentage 8.50% 8.50%
6.375% senior notes due 2028 | Senior Notes    
Long-Term Debt Repayments [Roll Forward]    
Total borrowings at face value, beginning balance $ 578  
Total repayments (578)  
Total borrowings at face value, ending balance $ 0 $ 578
Debt instrument interest rate stated percentage 6.375% 6.375%
7.150% debentures due 2028 | Debentures    
Long-Term Debt Repayments [Roll Forward]    
Total borrowings at face value, beginning balance $ 232  
Total repayments (232)  
Total borrowings at face value, ending balance $ 0 $ 232
Debt instrument interest rate stated percentage 7.15% 7.15%
7.200% senior debentures due 2028 | Senior Notes    
Long-Term Debt Repayments [Roll Forward]    
Total borrowings at face value, beginning balance $ 82  
Total repayments (82)  
Total borrowings at face value, ending balance $ 0 $ 82
Debt instrument interest rate stated percentage 7.20% 7.20%
3.500% senior notes due 2029 | Senior Notes    
Long-Term Debt Repayments [Roll Forward]    
Total borrowings at face value, beginning balance $ 286  
Total repayments (286)  
Total borrowings at face value, ending balance $ 0 $ 286
Debt instrument interest rate stated percentage 3.50% 3.50%
5.200% senior notes due 2029 | Senior Notes    
Long-Term Debt Repayments [Roll Forward]    
Total borrowings at face value, beginning balance $ 1,200  
Total repayments (1,200)  
Total borrowings at face value, ending balance $ 0 $ 1,200
Debt instrument interest rate stated percentage 5.20% 5.20%
7.950% debentures due 2029 | Senior Notes    
Long-Term Debt Repayments [Roll Forward]    
Total repayments $ (14)  
7.950% debentures due 2029 | Debentures    
Long-Term Debt Repayments [Roll Forward]    
Total borrowings at face value, beginning balance 116  
Total borrowings at face value, ending balance $ 102 $ 116
Debt instrument interest rate stated percentage 7.95% 7.95%
6.625% senior notes due 2030 | Senior Notes    
Long-Term Debt Repayments [Roll Forward]    
Total borrowings at face value, beginning balance $ 1,449  
Total repayments (381)  
Total borrowings at face value, ending balance $ 1,068 $ 1,449
Debt instrument interest rate stated percentage 6.625% 6.625%
6.125% senior notes due 2031 | Senior Notes    
Long-Term Debt Repayments [Roll Forward]    
Total borrowings at face value, beginning balance $ 1,143  
Total repayments (845)  
Total borrowings at face value, ending balance $ 298 $ 1,143
Debt instrument interest rate stated percentage 6.125% 6.125%
Zero Coupon senior notes due 2036 | Senior Notes    
Long-Term Debt Repayments [Roll Forward]    
Total borrowings at face value, beginning balance $ 285  
Total repayments (22)  
Total borrowings at face value, ending balance 263 $ 285
0.000% loan due 2039 (CAD denominated)    
Long-Term Debt Repayments [Roll Forward]    
Total borrowings at face value, beginning balance 17  
Total borrowings at face value, ending balance 16 $ 17
0.000% loan due 2039 (CAD denominated) | Secured Debt    
Long-Term Debt Repayments [Roll Forward]    
Total repayments $ (1)  
Debt instrument interest rate stated percentage 0.00% 0.00%