Investment in Securities - Schedule of the Fair Values of Securities with Unrealized Losses (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Marketable Securities [Line Items]
AFS, Less than 12 months, Estimated Fair Value	$ 571,177	$ 328,196
AFS, Less than 12 months, Unrealized Losses	50,380	3,956
AFS, 12 months or more, Estimated Fair Value	15,095	0
AFS, 12 months or more, Unrealized Losses	2,602	0
AFS, Total Estimated Fair Value	586,272	328,196
AFS, Total Unrealized Losses	52,982	3,956
State and political subdivisions
Marketable Securities [Line Items]
AFS, Less than 12 months, Estimated Fair Value	177,339	60,083
AFS, Less than 12 months, Unrealized Losses	18,358	990
AFS, 12 months or more, Estimated Fair Value	0	0
AFS, 12 months or more, Unrealized Losses	0	0
AFS, Total Estimated Fair Value	177,339	60,083
AFS, Total Unrealized Losses	18,358	990
Mortgage-backed securities issued or guaranteed by U.S. government agencies or sponsored enterprises
Marketable Securities [Line Items]
AFS, Less than 12 months, Estimated Fair Value	163,657	163,652
AFS, Less than 12 months, Unrealized Losses	19,123	2,200
AFS, 12 months or more, Estimated Fair Value	15,095	0
AFS, 12 months or more, Unrealized Losses	2,602	0
AFS, Total Estimated Fair Value	178,752	163,652
AFS, Total Unrealized Losses	21,725	2,200
Corporate bonds
Marketable Securities [Line Items]
AFS, Less than 12 months, Estimated Fair Value	81,774	55,120
AFS, Less than 12 months, Unrealized Losses	9,686	272
AFS, 12 months or more, Estimated Fair Value	0	0
AFS, 12 months or more, Unrealized Losses	0	0
AFS, Total Estimated Fair Value	81,774	55,120
AFS, Total Unrealized Losses	9,686	$ 272
U.S. treasury bonds
Marketable Securities [Line Items]
AFS, Less than 12 months, Estimated Fair Value	98,562
AFS, Less than 12 months, Unrealized Losses	954
AFS, 12 months or more, Estimated Fair Value	0
AFS, 12 months or more, Unrealized Losses	0
AFS, Total Estimated Fair Value	98,562
AFS, Total Unrealized Losses	$ 954