Investment Securities - Schedule of Amortized Cost and Fair Value of Debt Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Amortized cost
Due in one year or less	$ 64,776	$ 4,277
Due in one to five years	75,996	161,556
Due in five to ten years	51,162	61,290
Due in over ten years	391,270	234,720
Amortized cost, sub-total	583,204	461,843
Total debt securities	1,658,779	1,705,574
Fair value
Due in one year or less	64,279	4,225
Due in one to five years	71,801	152,181
Due in five to ten years	49,630	57,859
Due in over ten years	372,331	205,084
Fair value, sub-total	558,041	419,349
Total debt securities	1,471,973	1,471,186
Mortgage-backed securities - residential
Amortized cost
Mortgage-backed securities	1,057,389	1,224,522
Total debt securities	1,057,389	1,224,522
Fair value
Mortgage-backed securities	896,971	1,034,193
Total debt securities	896,971	1,034,193
Mortgage-backed securities - commercial
Amortized cost
Mortgage-backed securities	18,186	19,209
Total debt securities	18,186	19,209
Fair value
Mortgage-backed securities	16,961	17,644
Total debt securities	$ 16,961	$ 17,644