Investment Securities - Summary of Investment Security Carrying and Fair Value (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 266,055	$ 307,843
Gross Unrealized Gains	400	558
Gross Unrealized Losses	2,331	1,382
Fair Value	264,124	307,019
U.S. Treasury and government sponsored entities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	210,973	250,794
Gross Unrealized Gains	13	3
Gross Unrealized Losses	2,294	1,336
Fair Value	208,692	249,461
Municipal securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	11,938	14,395
Gross Unrealized Gains	22	72
Gross Unrealized Losses	25	46
Fair Value	11,935	14,421
Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	37,143	36,654
Gross Unrealized Gains	358	478
Gross Unrealized Losses	11	0
Fair Value	37,490	37,132
Collateralized loan obligations
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	6,001	6,000
Gross Unrealized Gains	7	5
Gross Unrealized Losses	1	0
Fair Value	$ 6,007	$ 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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-Name Accounting Standards Codification
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