Long-term borrowings (Details Textual) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Long-term Federal Home Loan Bank Advances	$ 43.0	$ 3.8
Long-term investments	$ 2.3	2.3
Debenture maturity date	Dec. 31, 2036
Residential mortgage, commercial real estate, and multi-family loans	$ 587.1	$ 552.6
Additional borrowing limit	$ 519.1
Weighted Average
Debt Instrument [Line Items]
Weighted average interest rate	0.72%
Weighted Average \| Long-term Debt
Debt Instrument [Line Items]
Weighted average interest rate	1.78%

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

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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

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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Amount of the collateral pledged in support of federal home loan bank advances outstanding.

+ References

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

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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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