Securities (Held to maturity securities losses) (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Fair Value
Less than 12 months	$ 30,496	$ 8,512
12 months or longer	7,907	8,989
Total	38,403	17,501
Unrealized Losses
Less than 12 months	(272)	(49)
12 months or longer	(555)	(467)
Total	(827)	(516)
Obligations of states and political subdivisions
Fair Value
Less than 12 months	30,496	8,512
12 months or longer	7,907	8,989
Total	38,403	17,501
Unrealized Losses
Less than 12 months	(272)	(49)
12 months or longer	(555)	(467)
Total	$ (827)	$ (516)

Amount of accumulated unrealized loss on investments in debt securities classified as held-to-maturity 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 7
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27337-111563

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-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27290-111563

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Amount of accumulated unrealized loss on investments in debt securities classified as held-to-maturity in a continuous loss position.

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Amount of accumulated unrealized loss on investments in debt securities classified as held-to-maturity that have been in a continuous loss position for less than twelve months.

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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)(1)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27290-111563

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-Publisher FASB
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27337-111563

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