Long-term borrowings (Details Textual) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Long-term Federal Home Loan Bank Advances	$ 40.0	$ 67.0
Long-term investments	$ 9.6	$ 9.4
Debenture maturity date	Dec. 31, 2036
Weighted average interest rate of debentures	1.89%	1.99%
Additional borrowing limit	$ 579.9
Weighted Average \| Long-term Debt
Debt Instrument [Line Items]
Weighted average interest rate	1.79%	1.39%

Additional federal home loan bank advances to be borrow under collateral pledge.

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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.

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in YYYY-MM-DD format.

+ References

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- Definition

States the interest rate applicable to Federal Home Loan Bank advances outstanding as of the Balance Sheet date.

+ References

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Including both current and noncurrent portions, Federal Home Loan Bank borrowings initially due beyond one year or beyond the normal operating cycle if longer.

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The total amount of investments that are intended to be held for an extended period of time (longer than one operating cycle).

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Weighted average interest rate of long-term debt outstanding calculated at point in time.

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