Allowance for credit losses - Allowance for loan losses - Additional Information (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Financing Receivable
Accumulated loans modified to borrowers under financial difficulties		$ 1,644,647
Commercial
Financing Receivable
Accumulated loans modified to borrowers under financial difficulties		324,425
Outstanding commitments to lend additional funds to debtors owing receivables whose terms have been modified in troubled debt restructurings	$ 7,000	$ 12,000

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.

No definition available.

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- Definition

Amount of financing receivable modified as troubled debt restructuring.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI https://asc.fasb.org/extlink&oid=123577603&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 https://asc.fasb.org/extlink&oid=121585226&loc=d3e18845-111554

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- Definition

Amount of unfunded portion of contractual agreement to lend funds to borrower for financing receivable modified as troubled debt restructuring.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=121585226&loc=d3e18794-111554

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