Loans, Allowance for Loan Losses, and Credit Quality - Summary of allowance for loan losses (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	$ 13,153	$ 12,653	$ 12,653
Provision for loan losses	900	1,360	1,600
Charge-offs	(629)	(1,110)	(1,213)
Recoveries	196	89	113
Net (charge-offs) recoveries	(433)	(1,021)	(1,100)
Ending balance	$ 13,620	$ 12,992	$ 13,153

Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount, after recoveries, of loans and leases that have been written-off.

+ References

No definition available.

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- Definition

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

+ References

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- Definition

Amount of expense related to estimated loss from loan and lease transactions.

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