Annual report pursuant to Section 13 and 15(d)

Securities - Summary of Debt Securities Available for Sale in an Unrealized Loss Position for Which an Allowance for Credit Losses Has Not Been Recorded (Detail)

v3.22.4
Securities - Summary of Debt Securities Available for Sale in an Unrealized Loss Position for Which an Allowance for Credit Losses Has Not Been Recorded (Detail)
$ in Thousands
Dec. 31, 2022
USD ($)
Security
Dec. 31, 2021
USD ($)
Security
Summary of Investment Holdings [Line Items]    
Available-for-Sale Within One Year, Gross Unrealized Loss $ (4,324) $ (9,953)
Available-for-Sale Within One Year, Estimated Fair Value $ 129,210 $ 800,439
Available-for-Sale Within One Year, Number of Securities | Security 49 158
Available-for-Sale More than One Year, Gross Unrealized Loss $ (120,697) $ (2,088)
Available-for-Sale More than One Year, Estimated Fair Value $ 719,787 $ 76,905
Available-for-Sale More than One Year, Number of Securities | Security 184 15
Available-for-Sale, Gross Unrealized Loss $ (125,021) $ (12,041)
Available-for-Sale, Estimated Fair Value $ 848,997 $ 877,344
Available-for-Sale, Number of Securities | Security 233 173
U.S. Treasury securities    
Summary of Investment Holdings [Line Items]    
Available-for-Sale Within One Year, Gross Unrealized Loss $ (414) $ (61)
Available-for-Sale Within One Year, Estimated Fair Value $ 33,812 $ 8,391
Available-for-Sale Within One Year, Number of Securities | Security 14 2
Available-for-Sale More than One Year, Gross Unrealized Loss $ (1,250)  
Available-for-Sale More than One Year, Estimated Fair Value $ 14,215  
Available-for-Sale More than One Year, Number of Securities | Security 4  
Available-for-Sale, Gross Unrealized Loss $ (1,664) $ (61)
Available-for-Sale, Estimated Fair Value $ 48,027 $ 8,391
Available-for-Sale, Number of Securities | Security 18 2
Mortgage-backed securities - residential    
Summary of Investment Holdings [Line Items]    
Available-for-Sale Within One Year, Gross Unrealized Loss $ (1,712) $ (5,484)
Available-for-Sale Within One Year, Estimated Fair Value $ 36,009 $ 498,731
Available-for-Sale Within One Year, Number of Securities | Security 18 92
Available-for-Sale More than One Year, Gross Unrealized Loss $ (73,789) $ (965)
Available-for-Sale More than One Year, Estimated Fair Value $ 424,302 $ 41,236
Available-for-Sale More than One Year, Number of Securities | Security 105 8
Available-for-Sale, Gross Unrealized Loss $ (75,501) $ (6,449)
Available-for-Sale, Estimated Fair Value $ 460,311 $ 539,967
Available-for-Sale, Number of Securities | Security 123 100
Mortgage-backed securities - commercial    
Summary of Investment Holdings [Line Items]    
Available-for-Sale Within One Year, Gross Unrealized Loss $ (84) $ (768)
Available-for-Sale Within One Year, Estimated Fair Value $ 4,069 $ 36,879
Available-for-Sale Within One Year, Number of Securities | Security 1 10
Available-for-Sale More than One Year, Gross Unrealized Loss $ (10,423) $ (689)
Available-for-Sale More than One Year, Estimated Fair Value $ 47,221 $ 18,221
Available-for-Sale More than One Year, Number of Securities | Security 14 3
Available-for-Sale, Gross Unrealized Loss $ (10,507) $ (1,457)
Available-for-Sale, Estimated Fair Value $ 51,290 $ 55,100
Available-for-Sale, Number of Securities | Security 15 13
Collateralized mortgage obligations    
Summary of Investment Holdings [Line Items]    
Available-for-Sale Within One Year, Gross Unrealized Loss $ (1,011) $ (1,256)
Available-for-Sale Within One Year, Estimated Fair Value $ 23,606 $ 76,894
Available-for-Sale Within One Year, Number of Securities | Security 8 16
Available-for-Sale More than One Year, Gross Unrealized Loss $ (11,740) $ (334)
Available-for-Sale More than One Year, Estimated Fair Value $ 61,879 $ 12,548
Available-for-Sale More than One Year, Number of Securities | Security 20 3
Available-for-Sale, Gross Unrealized Loss $ (12,751) $ (1,590)
Available-for-Sale, Estimated Fair Value $ 85,485 $ 89,442
Available-for-Sale, Number of Securities | Security 28 19
Debt securities    
Summary of Investment Holdings [Line Items]    
Available-for-Sale Within One Year, Gross Unrealized Loss $ (1,103) $ (1,503)
Available-for-Sale Within One Year, Estimated Fair Value $ 31,714 $ 110,996
Available-for-Sale Within One Year, Number of Securities | Security 8 21
Available-for-Sale More than One Year, Gross Unrealized Loss $ (10,736) $ (100)
Available-for-Sale More than One Year, Estimated Fair Value $ 106,785 $ 4,900
Available-for-Sale More than One Year, Number of Securities | Security 22 1
Available-for-Sale, Gross Unrealized Loss $ (11,839) $ (1,603)
Available-for-Sale, Estimated Fair Value $ 138,499 $ 115,896
Available-for-Sale, Number of Securities | Security 30 22
Total U.S. government agency and sponsored agency obligations    
Summary of Investment Holdings [Line Items]    
Available-for-Sale Within One Year, Gross Unrealized Loss $ (3,910) $ (9,011)
Available-for-Sale Within One Year, Estimated Fair Value $ 95,398 $ 723,500
Available-for-Sale Within One Year, Number of Securities | Security 35 139
Available-for-Sale More than One Year, Gross Unrealized Loss $ (106,688) $ (2,088)
Available-for-Sale More than One Year, Estimated Fair Value $ 640,187 $ 76,905
Available-for-Sale More than One Year, Number of Securities | Security 161 15
Available-for-Sale, Gross Unrealized Loss $ (110,598) $ (11,099)
Available-for-Sale, Estimated Fair Value $ 735,585 $ 800,405
Available-for-Sale, Number of Securities | Security 196 154
Municipal bonds-tax exempt    
Summary of Investment Holdings [Line Items]    
Available-for-Sale Within One Year, Gross Unrealized Loss   $ (881)
Available-for-Sale Within One Year, Estimated Fair Value   $ 68,548
Available-for-Sale Within One Year, Number of Securities | Security   17
Available-for-Sale More than One Year, Gross Unrealized Loss $ (12,759)  
Available-for-Sale More than One Year, Estimated Fair Value $ 65,385  
Available-for-Sale More than One Year, Number of Securities | Security 19  
Available-for-Sale, Gross Unrealized Loss $ (12,759) $ (881)
Available-for-Sale, Estimated Fair Value $ 65,385 $ 68,548
Available-for-Sale, Number of Securities | Security 19 17