Investment Securities - Summary of Carrying Amounts of Securities and Their Approximate Fair Values (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Schedule of Available for Sale Securities and Held to Maturity Securities [Line Items]
Available for sale securities, Amortized Cost	$ 211,990	$ 234,252
Available for sale securities, Gross Unrealized Gains	2,469	3,184
Available for sale securities, Gross Unrealized Losses	(2,193)	(406)
Available for sale securities, Fair Value	212,266	237,030
Held to maturity securities, Amortized Cost	492,782	247,672
Held to maturity securities, Gross Unrealized Gains	10,302	12,624
Held to maturity securities, Gross Unrealized Losses	(3,199)	(157)
Held to maturity securities, Fair Value	499,885	260,139
Total, Amortized Cost	704,772	481,924
Total, Gross Unrealized Gains	12,771	15,808
Total, Gross Unrealized Losses	(5,392)	(563)
Total, Fair Value	712,151	497,169
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	22,996	22,995
Available for sale securities, Gross Unrealized Gains	578	641
Available for sale securities, Gross Unrealized Losses	(159)	(19)
Available for sale securities, Fair Value	23,415	23,617
Corporate Debt Securities
Schedule of Available for Sale Securities and Held to Maturity Securities [Line Items]
Available for sale securities, Amortized Cost	1,742	2,742
Available for sale securities, Gross Unrealized Gains	38	41
Available for sale securities, Gross Unrealized Losses	(1)
Available for sale securities, Fair Value	1,779	2,783
Held to maturity securities, Amortized Cost	6,993	6,989
Held to maturity securities, Gross Unrealized Gains	110	197
Held to maturity securities, Fair Value	7,103	7,186
Mortgage Backed Securities
Schedule of Available for Sale Securities and Held to Maturity Securities [Line Items]
Available for sale securities, Amortized Cost	187,252	208,515
Available for sale securities, Gross Unrealized Gains	1,853	2,502
Available for sale securities, Gross Unrealized Losses	(2,033)	(387)
Available for sale securities, Fair Value	187,072	210,630
Held to maturity securities, Amortized Cost	379,726	137,435
Held to maturity securities, Gross Unrealized Gains	5,681	6,784
Held to maturity securities, Gross Unrealized Losses	(2,798)	(97)
Held to maturity securities, Fair Value	382,609	144,122
Municipal Securities
Schedule of Available for Sale Securities and Held to Maturity Securities [Line Items]
Held to maturity securities, Amortized Cost	106,063	103,248
Held to maturity securities, Gross Unrealized Gains	4,511	5,643
Held to maturity securities, Gross Unrealized Losses	(401)	(60)
Held to maturity securities, Fair Value	$ 110,173	$ 108,831

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Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

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