v3.25.1
Cover - shares
 3 Months Ended
Mar. 31, 2025
Apr. 30, 2025
Document Information [Line Items]    
Document Type 10-Q  
Document Quarterly Report true  
Document Period End Date Mar. 31, 2025  
Document Transition Report false  
Entity File Number 000-51404  
Entity Registrant Name FEDERAL HOME LOAN BANK OF INDIANAPOLIS  
Entity Tax Identification Number 35-6001443  
Entity Address, Address Line One 8250 Woodfield Crossing Blvd.  
Entity Address, City or Town Indianapolis  
Entity Address, State or Province IN  
Entity Address, Postal Zip Code 46240  
City Area Code 317  
Local Phone Number 465-0200  
Entity Current Reporting Status Yes  
Entity Interactive Data Current Yes  
Entity Filer Category Non-accelerated Filer  
Entity Emerging Growth Company false  
Entity Small Business false  
Entity Shell Company false  
Entity Central Index Key 0001331754  
Current Fiscal Year End Date --12-31  
Document Fiscal Year Focus 2025  
Document Fiscal Period Focus Q1  
Amendment Flag false  
Entity Incorporation, State or Country Code X1  
Class A    
Document Information [Line Items]    
Entity Common Stock, Outstanding (in shares)   0
Class B    
Document Information [Line Items]    
Entity Common Stock, Outstanding (in shares)   28,379,960