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Goodwill and intangible assets - Narrative (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2020 | Mar. 31, 2020 | Sep. 30, 2019
Mortgage Segment |  |  |
Finite-Lived Intangible Assets [Line Items] |  |  |
Relief of goodwill |  |  | $ 100
Farmers National | Core deposit intangible |  |  |
Finite-Lived Intangible Assets [Line Items] |  |  |
Finite-lived intangible assets acquired |  | $ 2,490 |
Estimated useful life of intangible assets | 4 years | 4 years |

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- Definition Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275 + Details
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