Investment Securities - Schedule of Amortized Cost and Fair Value by Contractual Maturity of Available-For-Sale Securities (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 266,055	$ 307,843
Fair Value	264,124	307,019
Fair Value, equity securities	6,006	5,731
U.S. Treasury and government sponsored entities
Debt Securities, Available-for-sale [Line Items]
Within 1 year, amortized cost	52,510
1-5 years, amortized cost	155,133
5-10 years, amortized cost	3,330
Amortized Cost	210,973	250,794
Within 1 year, fair value	52,396
1-5 years, fair value	152,981
5-10 years, fair value	3,315
Fair Value	$ 208,692	249,461
Within 1 year, weighted average yield	1.08%
1-5 years, weighted average yield	1.76%
5-10 years, weighted average yield	3.00%
Weighted Average Yield	1.61%
Corporate bonds
Debt Securities, Available-for-sale [Line Items]
1-5 years, amortized cost	$ 21,700
5-10 years, amortized cost	15,443
Amortized Cost	37,143	36,654
1-5 years, fair value	21,904
5-10 years, fair value	15,586
Fair Value	$ 37,490	37,132
1-5 years, weighted average yield	3.20%
5-10 years, weighted average yield	3.44%
Weighted Average Yield	3.30%
Collateralized loan obligations
Debt Securities, Available-for-sale [Line Items]
5-10 years, amortized cost	$ 3,000
Over 10 years, amortized cost	3,001
Amortized Cost	6,001	6,000
5-10 years, fair value	2,999
Over 10 years, fair value	3,008
Fair Value	$ 6,007	6,005
5-10 years, weighted average yield	3.81%
Over 10 years, weighted average yield	4.11%
Weighted Average Yield	3.96%
Preferred stock
Debt Securities, Available-for-sale [Line Items]
Over 10 years, amortized cost, equity securities	$ 5,868
Amortized Cost, equity securities	5,868
Over 10 years, fair value, equity securities	6,006
Fair Value, equity securities	$ 6,006
Over 10 years, weighted average yield, equity securities	5.77%
Weighted Average Yield, equity securities	5.77%
Municipal securities
Debt Securities, Available-for-sale [Line Items]
Within 1 year, amortized cost	$ 2,607
1-5 years, amortized cost	9,331
Amortized Cost	11,938	14,395
Within 1 year, fair value	2,606
1-5 years, fair value	9,329
Fair Value	$ 11,935	$ 14,421
Within 1 year, weighted average yield	1.32%
1-5 years, weighted average yield	2.42%
Weighted Average Yield	2.18%

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

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