Fair value measurements - Quantitative Information About Level 3 Fair Value Measurements (Details) - Significant unobservable inputs (Level 3) $ in Thousands	Dec. 31, 2020 USD ($)
Discount rate
Fair value measurements
Significant unobservable input value	0.093
Minimum \| Prepayment speed
Fair value measurements
Significant unobservable input value	0.15
Maximum \| Prepayment speed
Fair value measurements
Significant unobservable input value	0.22
Weighted Average \| Prepayment speed
Fair value measurements
Significant unobservable input value	0.22
Discounted cash flow
Fair value measurements
Mortgage servicing rights	$ 3,001
Commercial \| Fair value of property or collateral
Fair value measurements
Fair value	$ 387

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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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.

+ References

No definition available.

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- Definition

Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Value of input used to measure servicing asset.

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