| Debt Outstanding | Debt outstanding at March 31, 2023 and December 31, 2022 was as follows: 
|  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  
|  |  | March 31, 2023 |  | December 31, 2022 |  
|  |  | (In millions) |  
| Commercial paper |  | $ | 406.2 |  |  | $ | 566.8 |  |  
|  |  |  |  |  |  
|  |  |  |  |  |  
|  |  |  |  |  |  
| Notes, 3.95%, due June 2023 |  | 400.0 |  |  | 400.0 |  |  
| Notes, 2.6%, due December 2024 |  | 750.0 |  |  | 750.0 |  |  
| Notes, 2.6%, due December 2025 |  | 400.0 |  |  | 400.0 |  |  
| Notes, 3.25%, due June 2026 |  | 275.0 |  |  | 275.0 |  |  
| Revolver |  | 175.0 |  |  | — |  |  
| Term loan, due August 2026 |  | 700.0 |  |  | 700.0 |  |  
| Notes, 5.10%, due December 2027 |  | 750.0 |  |  | 750.0 |  |  
| Debentures, 6.9%, due July 2028 |  | 125.0 |  |  | 125.0 |  |  
| Notes, 3.1%, due May 2030 |  | 600.0 |  |  | 600.0 |  |  
| Notes, 2.35%, due September 2031 |  | 1,000.0 |  |  | 1,000.0 |  |  
| Notes, 7.0%, due July 2037 |  | 250.0 |  |  | 250.0 |  |  
| Other |  | 0.2 |  |  | 0.4 |  |  
| Total debt |  | 5,831.4 |  |  | 5,817.2 |  |  
| Less short-term debt and current maturities |  | (815.1) |  |  | (967.2) |  |  
| Less unamortized discounts and debt issuance costs |  | (28.4) |  |  | (29.9) |  |  
| Total long-term debt, net |  | $ | 4,987.9 |  |  | $ | 4,820.1 |  |  |