v3.26.1
Goodwill and Other Intangible Assets - Changes in Carrying Value of Goodwill (Details) - USD ($)
$ in Thousands
 9 Months Ended 12 Months Ended
Dec. 31, 2023
Mar. 31, 2026
Mar. 31, 2025
Mar. 31, 2024
Goodwill [Roll Forward]        
Goodwill, beginning balance $ 2,598,095 $ 2,557,595 $ 2,557,595 $ 2,598,095
Impairment charge   (35,000) 0 (40,500)
Additions     0  
Goodwill, ending balance   2,522,595 2,557,595 2,557,595
K-12        
Goodwill [Roll Forward]        
Goodwill, beginning balance 1,184,877 1,184,877 1,184,877 1,184,877
Impairment charge   0   0
Additions     0  
Goodwill, ending balance   1,184,877 1,184,877 1,184,877
Higher Education        
Goodwill [Roll Forward]        
Goodwill, beginning balance 990,022 990,022 990,022 990,022
Impairment charge   0   0
Additions     0  
Goodwill, ending balance   990,022 990,022 990,022
Global Professional        
Goodwill [Roll Forward]        
Goodwill, beginning balance 249,809 209,309 209,309 249,809
Impairment charge 0 0   (40,500)
Additions     0  
Goodwill, ending balance   209,309 209,309 209,309
International        
Goodwill [Roll Forward]        
Goodwill, beginning balance $ 173,387 173,387 173,387 173,387
Impairment charge   (35,000)   0
Additions     0  
Goodwill, ending balance   $ 138,387 $ 173,387 $ 173,387