Portfolio loans and allowance for loan losses - Summary of TDR loans (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Restructured loans
Total loans	$ 5,707	$ 8,838
In compliance with modified terms
Restructured loans
Total loans	5,005	8,319
30-89 days past due
Restructured loans
Total loans		127
Included in non-performing loans
Restructured loans
Total loans	$ 702	$ 392

Amount of financing receivable modified as troubled debt restructuring.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953676-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=118939409&loc=d3e18845-111554

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