Investment Securities - Schedule of Amortized Cost and Fair Value by Contractual Maturity of Available-For-Sale Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 266,342	$ 307,843
Fair Value	264,193	307,019
U.S. Treasury and government sponsored entities
Debt Securities, Available-for-sale [Line Items]
Within 1 year, amortized cost	30,005
1-5 years, amortized cost	174,986
5-10 years, amortized cost	3,330
Amortized Cost	208,321	250,794
Within 1 year, fair value	29,969
1-5 years, fair value	172,576
5-10 years, fair value	3,287
Fair Value	$ 205,832	249,461
Within 1 year, weighted average yield	1.15%
1-5 years, weighted average yield	1.87%
5-10 years, weighted average yield	3.00%
Weighted Average Yield	1.79%
Corporate bonds
Debt Securities, Available-for-sale [Line Items]
1-5 years, amortized cost	$ 21,702
5-10 years, amortized cost	18,440
Amortized Cost	40,142	36,654
1-5 years, fair value	21,897
5-10 years, fair value	18,619
Fair Value	$ 40,516	37,132
1-5 years, weighted average yield	3.17%
5-10 years, weighted average yield	3.37%
Weighted Average Yield	3.26%
Collateralized loan obligations
Debt Securities, Available-for-sale [Line Items]
5-10 years, amortized cost	$ 3,000
Over 10 years, amortized cost	3,000
Amortized Cost	6,000	6,000
5-10 years, fair value	2,997
Over 10 years, fair value	3,005
Fair Value	$ 6,002	6,005
5-10 years, weighted average yield	3.77%
Over 10 years, weighted average yield	4.07%
Weighted Average Yield	3.92%
Municipal securities
Debt Securities, Available-for-sale [Line Items]
Within 1 year, amortized cost	$ 2,592
1-5 years, amortized cost	9,287
Amortized Cost	11,879	14,395
Within 1 year, fair value	2,591
1-5 years, fair value	9,252
Fair Value	$ 11,843	$ 14,421
Within 1 year, weighted average yield	2.05%
1-5 years, weighted average yield	2.41%
Weighted Average Yield	2.34%

Debt Securities, Available For Sale Securities After Five Through Ten Years Weighted Average Yield

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Debt Securities, Available For Sale Securities After One Through Five Years Weighted Average Yield

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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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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in sixth fiscal year through tenth fiscal year following latest fiscal year. Excludes interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date.

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