Investment Securities - Summary of Carrying Amounts of Securities and Their Approximate Fair Values (Details) - USD ($) $ in Thousands		Sep. 30, 2023	Dec. 31, 2022
Schedule of Available for Sale Securities and Held to Maturity Securities [Line Items]
Available for sale securities, Amortized Cost		$ 167,903	$ 182,027
Available for sale securities, Gross Unrealized Gains		1	7
Available for sale securities, Gross Unrealized Losses		(31,651)	(28,618)
Total available for sale securities		136,253	153,416
Held to maturity securities, Amortized Cost		980,591	1,051,997
Held to maturity securities, Gross Unrealized Gains		2	92
Held to maturity securities, Gross Unrealized Losses		(195,957)	(166,503)
Held-to-maturity securities, fair value		784,636	885,586
Total, Amortized Cost		1,148,494	1,234,024
Total, Gross Unrealized Gains		3	99
Total, Gross Unrealized Losses		(227,608)	(195,121)
Total, Fair Value		920,889	1,039,002
U.S. Government Sponsored Enterprise Obligations
Schedule of Available for Sale Securities and Held to Maturity Securities [Line Items]
Available for sale securities, Amortized Cost		22,998	22,997
Available for sale securities, Gross Unrealized Losses		(3,512)	(3,264)
Total available for sale securities		19,486	19,733
U.S. Treasury Notes
Schedule of Available for Sale Securities and Held to Maturity Securities [Line Items]
Held to maturity securities, Amortized Cost		4,023	3,970
Held to maturity securities, Gross Unrealized Gains
Held to maturity securities, Gross Unrealized Losses		(43)	(18)
Held-to-maturity securities, fair value		3,980	3,952
Corporate Debt Securities
Schedule of Available for Sale Securities and Held to Maturity Securities [Line Items]
Available for sale securities, Amortized Cost			996
Available for sale securities, Gross Unrealized Gains			4
Total available for sale securities			1,000
Held to maturity securities, Amortized Cost		250	250
Held to maturity securities, Gross Unrealized Losses		(4)	(6)
Held-to-maturity securities, fair value		246	244
Mortgage Backed Securities
Schedule of Available for Sale Securities and Held to Maturity Securities [Line Items]
Available for sale securities, Amortized Cost		144,905	158,034
Available for sale securities, Gross Unrealized Gains		1	3
Available for sale securities, Gross Unrealized Losses		(28,139)	(25,354)
Total available for sale securities	[1]	116,767	132,683
Held to maturity securities, Amortized Cost	[1]	890,160	951,372
Held to maturity securities, Gross Unrealized Gains		2	4
Held to maturity securities, Gross Unrealized Losses		(182,990)	(157,208)
Held-to-maturity securities, fair value		707,172	794,168
Municipal Securities
Schedule of Available for Sale Securities and Held to Maturity Securities [Line Items]
Held to maturity securities, Amortized Cost		86,158	96,405
Held to maturity securities, Gross Unrealized Gains			88
Held to maturity securities, Gross Unrealized Losses		(12,920)	(9,271)
Held-to-maturity securities, fair value		$ 73,238	$ 87,222

[1] Includes agency mortgage-backed pass-through securities and collateralized mortgage obligations issued by U.S. Government Sponsored Enterprises (“GSEs”) and U.S. government agencies, such as FNMA, FHLMC, and GNMA that are not rated by Moody’s or Standard & Poor's. Each security contains a guarantee by the issuing U.S. GSE or agency and therefore carries an implicit guarantee of the U.S. government. These have been categorized as AAA/AA/A.