v3.26.1
Fair Value Measurements (Details) - USD ($)
$ in Thousands
3 Months Ended 12 Months Ended
Mar. 31, 2026
Dec. 31, 2025
Fair Value Measurements    
Marketable Securities $ 561,413 $ 584,236
Maximum period for redemption 1 year 1 year
Marketable securities at cost $ 561,900 $ 583,900
Recurring | Fair Value    
Fair Value Measurements    
Marketable Securities 561,413 584,236
Investments in Other Companies 2,643 4,253
Cash and Cash Equivalents 65,841 122,673
Total Assets Measured at Fair Value 629,897 711,162
Recurring | Fair Value | Bonds and bond funds    
Fair Value Measurements    
Marketable Securities 521,186 487,699
Recurring | Fair Value | Commercial paper    
Fair Value Measurements    
Marketable Securities 40,227 96,537
Recurring | Level 1    
Fair Value Measurements    
Investments in Other Companies 2,643 4,253
Cash and Cash Equivalents 65,841 122,673
Total Assets Measured at Fair Value 68,484 126,926
Recurring | Level 2    
Fair Value Measurements    
Marketable Securities 561,413 584,236
Total Assets Measured at Fair Value 561,413 584,236
Recurring | Level 2 | Bonds and bond funds    
Fair Value Measurements    
Marketable Securities 521,186 487,699
Recurring | Level 2 | Commercial paper    
Fair Value Measurements    
Marketable Securities $ 40,227 $ 96,537