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Derivatives, Hedging Activities and Financial Instruments with Off-Balance Sheet Risk - Commitments (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2020
Fixed Letters of Credit [Member] | Unused lines of Credit [Member]
Company's contractual commitments due to letters of credit
Loan commitments	$ 111,348	$ 88,883
Variable Letters of Credit [Member] | Unused lines of Credit [Member]
Company's contractual commitments due to letters of credit
Loan commitments	320,120	316,298
Letter of Credit [Member] | Unused lines of Credit [Member]
Company's contractual commitments due to letters of credit
Loan commitments	431,468	$ 405,181
Revision of Prior Period, Adjustment [Member] | Accounting Standards Update 2016-13
Company's contractual commitments due to letters of credit
Provision for Unfunded Commitments	$ 1,700

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- Definition

Amount of provision for unfunded commitments.

+ 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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- 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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