Leases (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Leases
Operating lease cost	$ 1,140	$ 1,178	$ 3,438	$ 3,486
Operating cash flows from operating leases	$ 1,258	$ 1,279	$ 3,803	$ 3,791
Weighted average remaining lease term Operating leases	7 years 9 months 14 days	8 years 8 months 8 days	7 years 9 months 14 days	8 years 8 months 8 days
Weighted average discount rate Operating leases	2.36%	3.42%	2.36%	3.42%

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- Definition

Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability.

+ References

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-Publisher FASB
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- Definition

Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

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- Definition

Weighted average discount rate for operating lease calculated at point in time.

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- Definition

Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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