Number of securities in continuous unrealized loss position for more than 12 months.

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 amount by which the fair value of an investment in debt securities categorized as Held-to-maturity is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 8A
-URI http://asc.fasb.org/extlink&oid=82896770&loc=SL6284422-111562

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Investment securities - Additional Information (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2017 USD ($) security	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Available-for-sale and Held-to-maturity securities
Carrying value of securities pledged \| $	$ 163,936	$ 144,750
State and Municipals, Tax-exempt
Available-for-sale and Held-to-maturity securities
Number of securities in continuous unrealized loss positions 12 months or longer	7
U.S. Government-sponsored enterprises state and municipals
Available-for-sale and Held-to-maturity securities
Number of securities in continuous unrealized loss positions 12 months or longer	20
Other-than-temporary impairments recognized \| $	$ 0	$ 0	$ 0
Mortgage-backed Securities, U.S. Government-sponsored enterprises
Available-for-sale and Held-to-maturity securities
Number of securities in continuous unrealized loss positions 12 months or longer	17
U.S. Treasuries
Available-for-sale and Held-to-maturity securities
Number of securities in continuous unrealized loss positions 12 months or longer	1