Allowance for credit losses - T D R that subsequently defaulted (Details) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2022 USD ($) loans	Jun. 30, 2022 USD ($) loans
Financing Receivable, Modifications [Line Items]
Loan count \| loans	50	79
Recorded investment as of first default date \| $	$ 6,624	$ 8,728
Mortgages
Financing Receivable, Modifications [Line Items]
Loan count \| loans	32	38
Recorded investment as of first default date \| $	$ 3,830	$ 5,699
Commercial \| Commercial and Industrial
Financing Receivable, Modifications [Line Items]
Loan count \| loans	3	3
Recorded investment as of first default date \| $	$ 2,496	$ 2,496
Consumer \| Credit card
Financing Receivable, Modifications [Line Items]
Loan count \| loans	8	19
Recorded investment as of first default date \| $	$ 28	$ 135
Consumer \| Personal loans
Financing Receivable, Modifications [Line Items]
Loan count \| loans	7	19
Recorded investment as of first default date \| $	$ 270	$ 398

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- Definition

Number of financing receivable contracts modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI https://asc.fasb.org/extlink&oid=123577603&loc=SL6953682-111524

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- Definition

Amount of financing receivable modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-Subparagraph (a)(2)
-URI https://asc.fasb.org/extlink&oid=123577603&loc=SL6953682-111524

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