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Commitments and contingencies - Financial Instruments with Off-Balance Sheet Credit Risk (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Balance at end of period	$ 2,787,594	$ 1,105,742
Commitments to extend credit, excluding interest rate lock commitments
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Balance at end of period	2,719,996	1,086,173
Letters of credit
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Balance at end of period	$ 67,598	$ 19,569

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- Definition

The face amount of financial liabilities, which are not recognized in the financial statements (off-balance sheet) because they fail to meet some other criterion for recognition.

+ References

No definition available.

+ Details

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- Definition

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.

+ Details

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- Details

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Period Type:

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- Details

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