Annual report [Section 13 and 15(d), not S-K Item 405]

Securities - Additional Information (Detail)

v3.25.4
Securities - Additional Information (Detail) - USD ($)
12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Debt Securities, Available-for-sale [Line Items]    
Unrealized loss on securities $ 0  
Pledged loans receivable, carrying value 2,400,000,000  
Securities available for sale pledged to secure advances $ 0 $ 29,400,000
Minimum | U.S. Government and its Agencies    
Debt Securities, Available-for-sale [Line Items]    
Holdings of securities as percentage of share holders' equity 10.00%