Investment Securities - Summary of Investment Security Carrying and Fair Value (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 313,265	$ 331,812
Gross Unrealized Gains	896	520
Gross Unrealized Losses	1,411	1,113
Fair Value	312,750	331,219
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	0	899
Gross Unrealized Gains		23
Gross Unrealized Losses		0
Fair Value		922
U.S. Treasury and government sponsored entities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	250,794	264,267
Gross Unrealized Gains	3	150
Gross Unrealized Losses	1,336	1,056
Fair Value	249,461	263,361
Municipal securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	14,395	18,184
Gross Unrealized Gains	72	26
Gross Unrealized Losses	46	53
Fair Value	14,421	18,157
U.S. Agency mortgage-backed securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		2
Gross Unrealized Gains		0
Gross Unrealized Losses		0
Fair Value		2
Corporate bonds
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	36,654	44,437
Gross Unrealized Gains	478	295
Gross Unrealized Losses	0	0
Fair Value	37,132	44,732
Collateralized loan obligations
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	6,000
Gross Unrealized Gains	5
Gross Unrealized Losses	0
Fair Value	6,005
Preferred stock
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	5,422	4,922
Gross Unrealized Gains	338	49
Gross Unrealized Losses	29	4
Fair Value	$ 5,731	4,967
Municipal securities
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost		899
Gross Unrealized Gains		23
Gross Unrealized Losses		0
Fair Value		$ 922

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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