v3.26.1
Goodwill - Changes in Goodwill by Reportable Segments (Detail)
$ in Thousands
3 Months Ended 12 Months Ended
Mar. 31, 2026
USD ($)
segment
Dec. 31, 2025
USD ($)
Goodwill [Roll Forward]    
Beginning balance $ 7,545,095 $ 7,375,216
Acquisitions 30,640 71,684
Foreign currency and other adjustments 6,578 98,195
Ending balance 7,582,313 7,545,095
Goodwill, before accumulated impairment charges 7,736,574  
Accumulated impairment charges (154,261)  
Ending balance 7,582,313 7,545,095
U. S. Dialysis    
Goodwill [Roll Forward]    
Beginning balance 6,527,616 6,517,220
Acquisitions 21,098 10,396
Foreign currency and other adjustments 0 0
Ending balance 6,548,714 6,527,616
Goodwill, before accumulated impairment charges 6,548,714  
Accumulated impairment charges 0  
Ending balance 6,548,714 6,527,616
Other - Ancillary Services    
Goodwill [Roll Forward]    
Beginning balance 1,017,479 857,996
Acquisitions 9,542 61,288
Foreign currency and other adjustments 6,578 98,195
Ending balance 1,033,599 1,017,479
Goodwill, before accumulated impairment charges 1,187,860  
Accumulated impairment charges (154,261)  
Ending balance $ 1,033,599 $ 1,017,479
Other Reporting Units    
Goodwill [Roll Forward]    
Number of operating segments that were considered at risk of significant goodwill impairment | segment 0