Investment Securities - Unrealized Gain (Loss) on Investments (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Debt Securities, Available-for-sale [Line Items]
Less than 12 months, fair value	$ 29,262	$ 41,201
Less than 12 months, unrealized losses	120	507
More than 12 months, fair value	134,527	137,480
More than 12 months, unrealized losses	853	1,455
Fair Value	163,789	178,681
Unrealized Losses	973	1,962
U.S. Treasury and government sponsored entities
Debt Securities, Available-for-sale [Line Items]
Less than 12 months, fair value	6,380	5,030
Less than 12 months, unrealized losses	3	6
More than 12 months, fair value	133,117	135,807
More than 12 months, unrealized losses	836	1,433
Fair Value	139,497	140,837
Unrealized Losses	839	1,439
Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Less than 12 months, fair value	11,963	22,285
Less than 12 months, unrealized losses	46	397
More than 12 months, fair value	0	0
More than 12 months, unrealized losses	0	0
Fair Value	11,963	22,285
Unrealized Losses	46	397
Collateralized loan obligations
Debt Securities, Available-for-sale [Line Items]
Less than 12 months, fair value	10,919	13,886
Less than 12 months, unrealized losses	71	104
More than 12 months, fair value	0	0
More than 12 months, unrealized losses	0	0
Fair Value	10,919	13,886
Unrealized Losses	71	104
Municipal securities
Debt Securities, Available-for-sale [Line Items]
Less than 12 months, fair value	0	0
Less than 12 months, unrealized losses	0	0
More than 12 months, fair value	1,410	1,673
More than 12 months, unrealized losses	17	22
Fair Value	1,410	1,673
Unrealized Losses	$ 17	$ 22

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27337-111563

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Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position.

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-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 6
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27290-111563

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