Investment Securities - Unrealized Gain (Loss) on Investments (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Schedule of Available-for-sale Securities [Line Items]
Less than 12 months, fair value	$ 187,288	$ 192,171
Less than 12 months, unrealized losses	752	1,084
More than 12 months, fair value	2,271	3,313
More than 12 months, unrealized losses	27	29
Fair Value	189,559	195,484
Unrealized Losses	779	1,113
U.S. Treasury and government sponsored entities
Schedule of Available-for-sale Securities [Line Items]
Less than 12 months, fair value	182,035	180,638
Less than 12 months, unrealized losses	737	1,051
More than 12 months, fair value	489	489
More than 12 months, unrealized losses	7	5
Fair Value	182,524	181,127
Unrealized Losses	744	1,056
Municipal Securities
Schedule of Available-for-sale Securities [Line Items]
Less than 12 months, fair value	4,217	11,533
Less than 12 months, unrealized losses	9	33
More than 12 months, fair value	1,782	1,786
More than 12 months, unrealized losses	20	20
Fair Value	5,999	13,319
Unrealized Losses	29	53
Preferred Stock
Schedule of Available-for-sale Securities [Line Items]
Less than 12 months, fair value	1,036	0
Less than 12 months, unrealized losses	6	0
More than 12 months, fair value	0	1,038
More than 12 months, unrealized losses	0	4
Fair Value	1,036	1,038
Unrealized Losses	$ 6	$ 4

Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale that have been in a continuous loss position for twelve months or longer.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27290-111563

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Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale in a continuous loss position.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-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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