Investment Securities - Summary of Investment Security Carrying and Fair Value (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 266,342	$ 307,843
Gross Unrealized Gains	387	558
Gross Unrealized Losses	2,536	1,382
Fair Value	264,193	307,019
U.S. Treasury and government sponsored entities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	208,321	250,794
Gross Unrealized Gains	0	3
Gross Unrealized Losses	2,489	1,336
Fair Value	205,832	249,461
Municipal securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	11,879	14,395
Gross Unrealized Gains	8	72
Gross Unrealized Losses	44	46
Fair Value	11,843	14,421
Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	40,142	36,654
Gross Unrealized Gains	374	478
Gross Unrealized Losses	0	0
Fair Value	40,516	37,132
Collateralized loan obligations
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	6,000	6,000
Gross Unrealized Gains	5	5
Gross Unrealized Losses	3	0
Fair Value	$ 6,002	$ 6,005

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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-SubTopic 10
-Section 50
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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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