Securities - Amortized cost and fair value of securities held to maturity by contractual maturity (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Amortized cost
Due after five years through ten years	$ 4,250
Due after ten years	6,433
Amortized Cost	10,683	$ 4,207
Fair value
Due after five years through ten years	4,256
Due after ten years	5,839
Fair Value	$ 10,095	$ 4,163

Held-to-Maturity Securities, Debt Maturities Year Five through Ten, Fair Value

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- Definition

Amount after other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (a)
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.1)
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-Publisher FASB
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-Subparagraph (SX 210.9-03.6)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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- Definition

Carrying amount of debt securities accounted for as held-to-maturity, net of adjustments including, but not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized, and fair value hedge accounting adjustments, maturing in the fifth through tenth fiscal year following the latest fiscal year.

+ References

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- Definition

Fair value of held-to-maturity debt securities maturing after the tenth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Carrying amount of debt securities accounted for as held-to-maturity, net of adjustments including, but not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized, and fair value hedge accounting adjustments, maturing after the tenth fiscal year following the latest fiscal year.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 320
-Section 50
-Paragraph 3
-Subparagraph (d)
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-Paragraph 5
-Subparagraph (f)(4)
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- Definition

Fair value of investments in debt securities classified as held-to-maturity.

+ References

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