XML 51 R40.htm IDEA: XBRL DOCUMENT v3.24.1.u1
Investment Securities, Equity Securities with Readily Determinable Fair Values and Other Investments (Details) - USD ($)
Mar. 31, 2024
Dec. 31, 2023
Held-to-maturity securities    
Amortized Value $ 4,400,000 $ 3,400,000
Estimated fair value 4,400,000 3,400,000
Carrying Value 4,400,000 3,400,000
Available-for-sale securities    
Amortized cost 5,306,234,000 5,330,814,000
Gross unrealized gains 4,437,000 11,143,000
Gross unrealized losses (541,041,000) (519,616,000)
Estimated fair value, Available for sale securities 4,769,630,000 4,822,341,000
Collateral Pledged    
Available-for-sale securities    
Amortized cost 1,821,695,000  
Estimated Fair Value    
Available-for-sale securities    
Estimated fair value, Available for sale securities 4,769,630,000 4,822,341,000
Reported Value Measurement    
Available-for-sale securities    
Estimated fair value, Available for sale securities 4,769,630,000 4,822,341,000
Residential mortgage-backed securities    
Available-for-sale securities    
Amortized cost 5,147,065,000 5,169,813,000
Gross unrealized gains 3,720,000 9,541,000
Gross unrealized losses (538,479,000) (519,255,000)
Residential mortgage-backed securities | Estimated Fair Value    
Available-for-sale securities    
Estimated fair value, Available for sale securities 4,612,306,000 4,660,099,000
Residential mortgage-backed securities | Reported Value Measurement    
Available-for-sale securities    
Estimated fair value, Available for sale securities 4,612,306,000 4,660,099,000
US Government Corporations and Agencies Securities [Member]    
Available-for-sale securities    
Estimated fair value, Available for sale securities 945,465,000 959,421,000
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]    
Available-for-sale securities    
Estimated fair value, Available for sale securities 3,666,841,000 3,700,678,000
States and political subdivisions    
Available-for-sale securities    
Amortized cost 159,169,000 161,001,000
Gross unrealized gains 717,000 1,602,000
Gross unrealized losses (2,562,000) (361,000)
States and political subdivisions | Estimated Fair Value    
Available-for-sale securities    
Estimated fair value, Available for sale securities 157,324,000 162,242,000
States and political subdivisions | Reported Value Measurement    
Available-for-sale securities    
Estimated fair value, Available for sale securities 157,324,000 162,242,000
Other Debt Obligations    
Held-to-maturity securities    
Amortized Value 4,400,000 3,400,000
Estimated fair value 4,400,000 3,400,000
Carrying Value $ 4,400,000 $ 3,400,000