XML 27 R1.htm IDEA: XBRL DOCUMENT v3.19.3
Cover Page - shares
 9 Months Ended
Sep. 30, 2019
Oct. 31, 2019
Entity Information [Line Items]    
Document Type 10-Q  
Amendment Flag false  
Document Quarterly Report true  
Document Period End Date Sep. 30, 2019  
Document Transition Report false  
Entity File Number 001-31924  
Entity Registrant Name NELNET, INC  
Entity Central Index Key 0001258602  
Current Fiscal Year End Date --12-31  
Document Fiscal Year Focus 2019  
Document Fiscal Period Focus Q3  
Entity Incorporation, State or Country Code NE  
Entity Tax Identification Number 84-0748903  
Entity Address, Address Line One 121 South 13th Street, Suite 100  
Entity Address, City or Town Lincoln,  
Entity Address, State or Province NE  
Entity Address, Postal Zip Code 68508  
City Area Code 402  
Local Phone Number 458-2370  
Title of 12(b) Security Class A Common Stock, Par Value $0.01 per Share  
Trading Symbol NNI  
Security Exchange Name NYSE  
Entity Current Reporting Status Yes  
Entity Interactive Data Current Yes  
Entity Filer Category Large Accelerated Filer  
Entity Small Business false  
Entity Emerging Growth Company false  
Entity Shell Company false  
Common Class A    
Entity Information [Line Items]    
Entity Common Stock, Shares Outstanding   28,416,724
Common Class B    
Entity Information [Line Items]    
Entity Common Stock, Shares Outstanding   11,279,641