v3.25.1
Advances - Schedule of Credit and Concentration Risk (Details) - USD ($)
$ in Millions
3 Months Ended
Mar. 31, 2025
Mar. 31, 2024
Dec. 31, 2024
Advances [Line Items]      
Advances Outstanding $ 37,954   $ 45,818
Top ten borrowers | Western Alliance Bank      
Advances [Line Items]      
Advances Outstanding 3,700 $ 5,750  
Interest Income from Advances $ 41 $ 44  
Top ten borrowers | Western Alliance Bank | Percentage of Total Advances Outstanding      
Advances [Line Items]      
Concentration risk (as a percent) 10.00% 10.00%  
Top ten borrowers | Western Alliance Bank | Percentage of Total Interest Income from Advances      
Advances [Line Items]      
Concentration risk (as a percent) 9.00% 7.00%  
Top ten borrowers | JPMorgan Chase      
Advances [Line Items]      
Advances Outstanding $ 3,374 $ 21,319  
Interest Income from Advances $ 70 $ 239  
Top ten borrowers | JPMorgan Chase | Percentage of Total Advances Outstanding      
Advances [Line Items]      
Concentration risk (as a percent) 9.00% 37.00%  
Top ten borrowers | JPMorgan Chase | Percentage of Total Interest Income from Advances      
Advances [Line Items]      
Concentration risk (as a percent) 16.00% 40.00%