Investment Securities - Available-for-sale (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 446,676	$ 400,718
Unrealized Gain	6,454	10,440
Unrealized Loss	(2,358)	(534)
Fair Value	450,772	410,624
Total debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	435,889	382,317
Unrealized Gain	6,276	10,294
Unrealized Loss	(2,322)	(463)
Fair Value	439,843	392,148
United States government agency securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	43,428	56,207
Unrealized Gain	341	995
Unrealized Loss	(567)	(210)
Fair Value	43,202	56,992
United States sponsored mortgage-backed securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	87,082	94,968
Unrealized Gain	340	972
Unrealized Loss	(1,186)	(171)
Fair Value	86,236	95,769
United States treasury securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	106,869
Unrealized Gain	78
Unrealized Loss	(291)
Fair Value	106,656
Municipal securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	191,010	223,642
Unrealized Gain	5,517	8,327
Unrealized Loss	(278)	(82)
Fair Value	196,249	231,887
Other debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	7,500	7,500
Unrealized Gain	0	0
Unrealized Loss	0	0
Fair Value	7,500	7,500
Other securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	10,787	18,401
Unrealized Gain	178	146
Unrealized Loss	(36)	(71)
Fair Value	$ 10,929	$ 18,476

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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Amount excluding accrued interest, 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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