v3.26.1
Loans and Accrued Interest Receivable and Allowance for Loan Losses - Schedule of Allowance for Loan Losses (Details) - USD ($)
$ in Thousands
 3 Months Ended 6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
Financing Receivable, Allowance for Credit Loss [Roll Forward]        
Balance at beginning of period $ 155,191 $ 120,076 $ 132,078 $ 114,890
Provision (negative provision) for loan losses 41,023 17,712 94,595 33,177
Charge-offs (34,923) (14,514) (67,610) (25,410)
Recoveries 3,774 1,015 6,002 1,632
Initial allowance on loans purchased with credit deterioration 0 1,060 0 1,060
Loan sales/contributions 0 0 0 0
Balance at end of period 165,065 125,349 165,065 125,349
Federally insured loans - Non-Nelnet Bank        
Financing Receivable, Allowance for Credit Loss [Roll Forward]        
Balance at beginning of period 40,043 48,906 42,080 49,091
Provision (negative provision) for loan losses 2,387 2,112 4,459 4,746
Charge-offs (2,687) (3,391) (5,655) (6,210)
Recoveries 0 0 0 0
Initial allowance on loans purchased with credit deterioration 0 0 0 0
Loan sales/contributions (1,570) 0 (2,711) 0
Balance at end of period 38,173 47,627 38,173 47,627
Private education loans - Non-Nelnet Bank        
Financing Receivable, Allowance for Credit Loss [Roll Forward]        
Balance at beginning of period 6,385 10,394 6,894 11,130
Provision (negative provision) for loan losses 0 (2,760) (306) (2,760)
Charge-offs (392) (523) (777) (1,457)
Recoveries 246 295 428 493
Initial allowance on loans purchased with credit deterioration 0 0 0 0
Loan sales/contributions 0 0 0 0
Balance at end of period 6,239 7,406 6,239 7,406
Consumer loans and other financing receivables - Non-Nelnet Bank        
Financing Receivable, Allowance for Credit Loss [Roll Forward]        
Balance at beginning of period 79,593 43,904 57,360 38,468
Provision (negative provision) for loan losses 38,939 11,781 85,639 22,158
Charge-offs (29,396) (7,967) (55,529) (13,143)
Recoveries 3,079 310 4,745 545
Initial allowance on loans purchased with credit deterioration 0 0 0 0
Loan sales/contributions 0 0 0 0
Balance at end of period 92,215 48,028 92,215 48,028
Federally insured loans - Nelnet Bank        
Financing Receivable, Allowance for Credit Loss [Roll Forward]        
Balance at beginning of period 1,725 362 676 0
Provision (negative provision) for loan losses (158) 9 (191) 374
Charge-offs (121) (16) (180) (19)
Recoveries 0 0 0 0
Initial allowance on loans purchased with credit deterioration 0 0 0 0
Loan sales/contributions 1,570 0 2,711 0
Balance at end of period 3,016 355 3,016 355
Private education loans - Nelnet Bank        
Financing Receivable, Allowance for Credit Loss [Roll Forward]        
Balance at beginning of period 13,182 9,893 12,932 10,086
Provision (negative provision) for loan losses 572 2,839 2,337 3,925
Charge-offs (1,498) (1,739) (3,291) (3,134)
Recoveries 353 307 631 423
Initial allowance on loans purchased with credit deterioration 0 1,060 0 1,060
Loan sales/contributions 0 0 0 0
Balance at end of period 12,609 12,360 12,609 12,360
Consumer and other loans - Nelnet Bank        
Financing Receivable, Allowance for Credit Loss [Roll Forward]        
Balance at beginning of period 14,263 6,617 12,136 6,115
Provision (negative provision) for loan losses (717) 3,731 2,657 4,734
Charge-offs (829) (878) (2,178) (1,447)
Recoveries 96 103 198 171
Initial allowance on loans purchased with credit deterioration 0 0 0 0
Loan sales/contributions 0 0 0 0
Balance at end of period $ 12,813 $ 9,573 $ 12,813 $ 9,573