v3.26.3
Related Party Transactions - Narrative (Details) - USD ($)
1 Months Ended 3 Months Ended 9 Months Ended
May 31, 2026
Sep. 30, 2026
Sep. 30, 2025
Sep. 30, 2026
Sep. 30, 2025
Dec. 31, 2025
Related Party Transaction [Line Items]            
Notional Amount of Derivatives   $ 181,220,832,000   $ 181,220,832,000   $ 198,855,637,000
Compensating balances   30,000,000.0   30,000,000.0   5,000,000.0
Related Party            
Related Party Transaction [Line Items]            
Mortgage-backed securities acquired       0 $ 0  
Notional Amount of Derivatives   0   0   0
Overnight loans extended to other FHLBanks   25,500,000   $ 25,500,000   8,400,000
Borrowing period from other FHLBanks       1 day    
Borrowings from other FHLBanks   0   $ 0   0
Annual lease receipt   100,000   100,000    
Related Party | Citibank, N.A.            
Related Party Transaction [Line Items]            
Compensating balances   30,000,000.0   30,000,000.0   5,000,000.0
Debt Assumptions | Related Party            
Related Party Transaction [Line Items]            
Amount of transaction       0 0  
Debt Transfers | Related Party            
Related Party Transaction [Line Items]            
Amount of transaction         0  
Debt Transfers | Related Party | Hedged Consolidated obligation bonds            
Related Party Transaction [Line Items]            
Amount of transaction $ 750,000,000          
Debt Transfers | Related Party | Hedged Consolidated obligation discount notes            
Related Party Transaction [Line Items]            
Amount of transaction $ 1,000,000,000.0          
Advances Sold or Transferred | Related Party            
Related Party Transaction [Line Items]            
Amount of transaction       0 0  
Mortgage Partnership Finance Program Services | Related Party | Federal Home Loan Bank of Chicago            
Related Party Transaction [Line Items]            
Amount of transaction   200,000 $ 300,000 700,000 $ 800,000  
Purchases of mortgage loans, cumulative participations by other Federal Home Loan Banks   $ 3,400,000   $ 3,400,000   $ 2,000,000.0