Other real estate owned - Narrative (Details) $ in Thousands	3 Months Ended	12 Months Ended
Dec. 31, 2017 USD ($) branch	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Real Estate Properties [Line Items]
Real estate acquired through merger		$ 0	$ 6,888	$ 0
Excess land and facilities transferred		0	3,466	$ 0
Other real estate owned included excess land and facilities held for sale		5,381	5,895
Clayton Bank and Trust and American City Bank
Real Estate Properties [Line Items]
Real estate acquired through merger			7,000
Excess land and facilities transferred	$ 3,466		4,147
Number of branch locations consolidated as part of merger or acquisition \| branch	5
Residential Real Estate Properties
Real Estate Properties [Line Items]
Foreclosed residential real estate properties	$ 3,631	2,101	3,631
Total foreclosure proceedings in process	$ 19	$ 478	$ 19

Number of branch locations consolidated.

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Real estate acquired through merger or acquisition.

+ References

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- Definition

Recorded investment of consumer mortgage loan receivables secured by residential real estate properties for which formal foreclosure proceedings are in process.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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-Paragraph 35
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The cash outflow from the acquisition of a piece of land held for sale, anything permanently fixed to it, including buildings, structures on it, and so forth.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-SubTopic 10
-Section 45
-Paragraph 13
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Amount of increase (decrease) of physical assets used in the normal conduct of business and not intended for resale, from reclassification, impairment, donation, or changes classified as other. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
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Carrying amount as of the balance sheet date of land and buildings obtained through foreclosure proceedings or defeasance in full or partial satisfaction of a debt arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
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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.

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