Investment Securities - Summary of Investment Security Carrying and Fair Value (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Available-for-sale Debt Securities, Amortized Cost Basis [Abstract]
Amortized Cost	$ 299,386	$ 307,843
Gross Unrealized Gains	346	558
Gross Unrealized Losses	2,159	1,382
Fair Value	297,573	307,019
U.S. Treasury and government sponsored entities
Available-for-sale Debt Securities, Amortized Cost Basis [Abstract]
Amortized Cost	245,429	250,794
Gross Unrealized Gains	0	3
Gross Unrealized Losses	2,111	1,336
Fair Value	243,318	249,461
Municipal securities
Available-for-sale Debt Securities, Amortized Cost Basis [Abstract]
Amortized Cost	13,805	14,395
Gross Unrealized Gains	18	72
Gross Unrealized Losses	47	46
Fair Value	13,776	14,421
Corporate bonds
Available-for-sale Debt Securities, Amortized Cost Basis [Abstract]
Amortized Cost	34,152	36,654
Gross Unrealized Gains	317	478
Gross Unrealized Losses	0	0
Fair Value	34,469	37,132
Collateralized loan obligations
Available-for-sale Debt Securities, Amortized Cost Basis [Abstract]
Amortized Cost	6,000	6,000
Gross Unrealized Gains	11	5
Gross Unrealized Losses	1	0
Fair Value	$ 6,010	$ 6,005

Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt securities classified as available-for-sale.

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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt securities classified as available-for-sale.

+ References

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This item represents the cost of debt securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.2)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Amount of debt securities categorized neither as held-to-maturity nor trading.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=75030427&loc=d3e22054-111558

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=82896770&loc=d3e26610-111562

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 320
-Section 50
-Paragraph 2
-Subparagraph (b)-(g)
-URI http://asc.fasb.org/extlink&oid=75019621&loc=d3e62557-112803

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