Investment securities - Restricted Investment In Stock (Details) $ in Thousands	6 Months Ended
Jun. 30, 2019 USD ($) security	Jun. 30, 2018 USD ($)
Available-for-sale and Held-to-maturity securities
Proceeds from sale of available-for-sale investment securities \| $	$ 9,677
Gross realized gains \| $	$ 23
Number of securities in continuous unrealized loss position	73
Other-than-temporary impairments recognized \| $	$ 0
State and Municipals, Tax-exempt
Available-for-sale and Held-to-maturity securities
Number of securities in continuous unrealized loss position	20
Number of securities in continuous unrealized loss positions 12 months or longer	20
U.S. Treasuries
Available-for-sale and Held-to-maturity securities
Number of securities in continuous unrealized loss position	3
Number of securities in continuous unrealized loss positions 12 months or longer	3
U.S. Government-sponsored enterprises state and municipals
Available-for-sale and Held-to-maturity securities
Number of securities in continuous unrealized loss position	28
Number of securities in continuous unrealized loss positions 12 months or longer	28
Other-than-temporary impairments recognized \| $	$ 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 position	22
Number of securities in continuous unrealized loss positions 12 months or longer	20

The number of securities in continuous unrealized loss position.

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- Definition

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

+ References

No definition available.

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- Definition

Amount of realized gain on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27357-111563

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Amount, before tax, of other-than-temporary impairment (OTTI) on investment in debt security measured at amortized cost (held-to-maturity), recognized in earnings and other comprehensive income (OCI).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 8A
-URI http://asc.fasb.org/extlink&oid=118954083&loc=SL6284422-111562

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Amount of cash inflow from sale of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=118954083&loc=d3e26853-111562

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3151-108585

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3179-108585

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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.

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