XML 47 R39.htm IDEA: XBRL DOCUMENT v3.24.2.u1
Investment Securities - Additional Information (Details)
 6 Months Ended
Jun. 30, 2024
USD ($)
Position
Security
Dec. 31, 2023
USD ($)
Position
Security
Schedule Of Available For Sale Securities [Line Items]    
Equity securities, at fair value $ 4,258,000 $ 4,074,000
Tax rate used to calculate tax-equivalent yields (in hundredths) 21.00%  
Percentage investment book value exceeds stockholders' equity (in hundredths) 10.00%  
Debt securities, available-for-sale, restricted $ 728,000,000 831,000,000
Available-for-sale, 12 months or longer, Fair Value 1,036,465,000 1,075,835,000
12 months or longer, unrealized losses $ 199,931,000 $ 192,616,000
U.S. Treasury Securities and Obligations of U.S. Government Corporations and Agencies    
Schedule Of Available For Sale Securities [Line Items]    
Number of securities in unrealized loss positions | Security 32 36
Available-for-sale, 12 months or longer, Fair Value $ 196,288,000 $ 210,069,000
12 months or longer, unrealized losses $ 25,248,000 $ 26,215,000
Held-to-maturity, securities in unrealized loss positions, qualitative disclosure, number of positions | Position 0 0
Obligations of States and Political Subdivisions    
Schedule Of Available For Sale Securities [Line Items]    
Number of securities in unrealized loss positions | Security 0 237
Available-for-sale, 12 months or longer, Fair Value $ 247,125,000 $ 241,630,000
12 months or longer, unrealized losses $ 56,082,000 $ 49,038,000
Mortgage-backed Securities: GSE Residential    
Schedule Of Available For Sale Securities [Line Items]    
Number of securities in unrealized loss positions | Security 250 263
Available-for-sale, 12 months or longer, Fair Value $ 535,856,000 $ 566,197,000
12 months or longer, unrealized losses $ 114,474,000 $ 113,007,000
Other Securities    
Schedule Of Available For Sale Securities [Line Items]    
Number of securities in unrealized loss positions | Security 40 43
Available-for-sale, 12 months or longer, Fair Value $ 57,196,000 $ 57,939,000
12 months or longer, unrealized losses $ 4,127,000 $ 4,356,000