Investment Securities - Schedule of Amortized Cost and Fair Value by Contractual Maturity of Available-For-Sale Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Schedule of Available-for-sale Securities [Line Items]
Fair Value	$ 297,573	$ 307,019
U.S. Treasury and government sponsored entities
Schedule of Available-for-sale Securities [Line Items]
Within 1 year, amortized cost	97,714
1-5 years, amortized cost	147,715
Amortized Cost	245,429
Within 1 year, fair value	97,467
1-5 years, fair value	145,851
Fair Value	$ 243,318	249,461
Within 1 year, weighted average yield	1.08%
1-5 years, weighted average yield	1.71%
Weighted Average Yield	1.46%
Corporate bonds
Schedule of Available-for-sale Securities [Line Items]
Within 1 year, amortized cost	$ 2,000
1-5 years, amortized cost	21,703
5-10 years, amortized cost	10,449
Amortized Cost	34,152
Within 1 year, fair value	2,000
1-5 years, fair value	21,891
5-10 years, fair value	10,578
Fair Value	$ 34,469	37,132
Within 1 year, weighted average yield	2.37%
1-5 years, weighted average yield	2.63%
5-10 years, weighted average yield	3.05%
Weighted Average Yield	2.74%
Collateralized loan obligations
Schedule of Available-for-sale Securities [Line Items]
1-5 years, amortized cost	$ 3,000
Over 10 years, amortized cost	3,000
Amortized Cost	6,000
1-5 years, fair value	2,999
Over 10 years, fair value	3,011
Fair Value	$ 6,010	6,005
1-5 years, weighted average yield	3.04%
Over 10 years, weighted average yield	3.51%
Weighted Average Yield	3.27%
Preferred stock
Schedule of Available-for-sale Securities [Line Items]
Over 10 years, amortized cost	$ 5,373
Amortized Cost	5,373
Over 10 years, fair value	5,527
Fair Value	$ 5,527
Over 10 years, weighted average yield	6.36%
Weighted Average Yield	6.36%
Municipal securities
Schedule of Available-for-sale Securities [Line Items]
Within 1 year, amortized cost	$ 3,202
1-5 years, amortized cost	10,603
Amortized Cost	13,805
Within 1 year, fair value	3,198
1-5 years, fair value	10,578
Fair Value	$ 13,776	$ 14,421
Within 1 year, weighted average yield	1.80%
1-5 years, weighted average yield	2.67%
Weighted Average Yield	2.47%