v3.26.1
Earnings per Common Share (Details) - USD ($)
$ / shares in Units, $ in Thousands
 3 Months Ended 6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]        
Net income attributable to Nelnet, Inc., basic $ 66,662 $ 181,459 $ 137,788 $ 264,018
Net income attributable to Nelnet, Inc., diluted $ 66,662 $ 181,459 $ 137,788 $ 264,018
Weighted-average common shares outstanding - basic (in shares) 36,037,509 36,485,605 36,057,102 36,482,035
Weighted-average common shares outstanding - diluted (in shares) 36,037,509 36,485,605 36,057,102 36,482,035
Earnings per share - basic (in dollars per share) $ 1.85 $ 4.97 $ 3.82 $ 7.24
Earnings per share - diluted (in dollars per share) $ 1.85 $ 4.97 $ 3.82 $ 7.24
Common shareholders        
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]        
Net income attributable to Nelnet, Inc., basic $ 65,433 $ 178,170 $ 135,287 $ 259,158
Net income attributable to Nelnet, Inc., diluted $ 65,433 $ 178,170 $ 135,287 $ 259,158
Weighted-average common shares outstanding - basic (in shares) 35,373,041 35,824,313 35,402,521 35,810,499
Weighted-average common shares outstanding - diluted (in shares) 35,373,041 35,824,313 35,402,521 35,810,499
Earnings per share - basic (in dollars per share) $ 1.85 $ 4.97 $ 3.82 $ 7.24
Earnings per share - diluted (in dollars per share) $ 1.85 $ 4.97 $ 3.82 $ 7.24
Unvested restricted stock shareholders        
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]        
Net income attributable to Nelnet, Inc., basic $ 1,229 $ 3,289 $ 2,501 $ 4,860
Net income attributable to Nelnet, Inc., diluted $ 1,229 $ 3,289 $ 2,501 $ 4,860
Weighted-average common shares outstanding - basic (in shares) 664,468 661,292 654,581 671,536
Weighted-average common shares outstanding - diluted (in shares) 664,468 661,292 654,581 671,536
Earnings per share - basic (in dollars per share) $ 1.85 $ 4.97 $ 3.82 $ 7.24
Earnings per share - diluted (in dollars per share) $ 1.85 $ 4.97 $ 3.82 $ 7.24