Other real estate owned - Narrative (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2019	Dec. 31, 2018
Real Estate Properties [Line Items]
Other real estate owned included excess land and facilities held for sale	$ 7,305
Residential Real Estate Properties
Real Estate Properties [Line Items]
Foreclosed residential real estate properties	3,066	$ 2,101
Total foreclosure proceedings in process	867	478
Atlantic Capital Bank
Real Estate Properties [Line Items]
Other real estate owned included excess land and facilities held for sale	$ 891	$ 5,381

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 35
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL49126937-111524

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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
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
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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
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5162-111524

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
-Topic 310
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No definition available.

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