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Investment Securities (Details Textual) $ in Thousands	12 Months Ended
	Dec. 31, 2017 USD ($) Investment	Dec. 31, 2016 USD ($) Investment	Dec. 31, 2015 USD ($)
Investment Securities (Textual)
Sale of investment securities	$ 9,700	$ 33,500
Gain on sale of investment securities	$ 4	$ 431	$ 297
Number of investments, Less than 12 months | Investment	25	63
Fair market value, less than 12 months	$ 27,800
Number of investments, 12 months or longer | Investment	28	2
Fair market value,12 months or longer	$ 27,500
Securities pledged as collateral for repurchase agreements from brokers	$ 7,700	$ 21,000
Securities pledged to secure client deposit		$ 21,100

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- Definition

Investment securities.

+ References

No definition available.

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- Definition

Investments with fair market value in continuous unrealized loss position for less than twelve months.

+ References

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- Definition

Investments with fair market value In continuous unrealized loss position twelve months or longer.

+ References

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- Definition

Number of investments in continuous unrealized loss position, less than twelve months.

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- Definition

Number of investments in continuous unrealized loss position twelve months or longer.

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- Definition

Securities pledged to secure client deposit.

+ References

No definition available.

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- Definition

The fair value of available-for-sale securities that serve as collateral for borrowings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5086-111524

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- Definition

The difference between the carrying value and the sale price of an investment. A gain would be recognized when the sale price of the investment is greater than the carrying value of the investment. This element refers to the Gain included in earnings and not to the cash proceeds of the sale.

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- Definition

The cash inflow associated with the sale of debt securities classified as available-for-sale securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=82896770&loc=d3e26853-111562

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3179-108585

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