Securities Available for Sale - Amortized costs and fair values of debt securities available for sale (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 492,606	$ 443,249
Gross Unrealized Gains	18,215	6,967
Gross Unrealized Losses	12	914
Fair Value	$ 510,809	$ 449,302
Fair Value as % of Total	100.00%	100.00%
U.S. government agency securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 63,512	$ 16,516
Gross Unrealized Gains	338	4
Gross Unrealized Losses	0	60
Fair Value	$ 63,850	$ 16,460
Fair Value as % of Total	12.00%	4.00%
State, county and municipals
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 162,239	$ 155,501
Gross Unrealized Gains	4,261	1,049
Gross Unrealized Losses	2	157
Fair Value	$ 166,498	$ 156,393
Fair Value as % of Total	33.00%	35.00%
Mortgage-backed securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 188,819	$ 193,223
Gross Unrealized Gains	8,087	2,492
Gross Unrealized Losses	10	697
Fair Value	$ 196,896	$ 195,018
Fair Value as % of Total	39.00%	43.00%
Corporate debt securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 78,036	$ 78,009
Gross Unrealized Gains	5,529	3,422
Gross Unrealized Losses	0	0
Fair Value	$ 83,565	$ 81,431
Fair Value as % of Total	16.00%	18.00%

Percentage Of Total, Debt Securities, Available-for-sale

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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).

+ References

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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).

+ References

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Amount 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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