Commitments and Contingencies - Contractual amount of off-balance sheet instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Commitments to extend credit
Financial instruments whose contract amounts represent credit risk:
Financial instruments	$ 2,079,644	$ 2,126,275
Letters of credit
Financial instruments whose contract amounts represent credit risk:
Financial instruments	$ 24,705	$ 22,533

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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