v3.26.3
Capital Stock and Earnings Per Share (OMH Only) - Schedule of Computation of Earnings Per Share (Details) - USD ($)
$ / shares in Units, $ in Millions
 3 Months Ended 9 Months Ended
Sep. 30, 2026
Sep. 30, 2025
Sep. 30, 2026
Sep. 30, 2025
Numerator (basic and diluted):        
Net income $ 185 $ 199 $ 563 $ 579
Denominator:        
Weighted average number of shares outstanding (basic) (in shares) 114,864,912 118,759,941 115,643,942 119,037,486
Effect of dilutive securities (in shares) 618,883 660,103 526,611 556,706
Weighted average number of shares outstanding (diluted) (in shares) 115,483,795 119,420,044 116,170,553 119,594,192
Earnings per share:        
Basic (in dollars per share) $ 1.61 $ 1.67 $ 4.87 $ 4.86
Diluted (in dollars per share) $ 1.60 $ 1.67 $ 4.85 $ 4.84
Restricted Stock Units        
Earnings per share:        
Shares excluded in the diluted earnings per share calculation (in shares) 450,017 472,402 466,154 498,509