UNAUDITED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 4,272	$ 6,111	$ 10,470	$ 11,916
Unrealized gains/(losses) on available for sale securities
Unrealized holding gains/(losses) arising during period	1,453	(423)	2,548	(1,775)
Less: reclassification adjustment for losses/(gains) included in net income	(4)	(2)	62	(2)
Total unrealized gains/(losses) on securities	1,449	(425)	2,610	(1,777)
Derivatives
Change in interest rate contracts	1,219		1,189
Defined benefit retirement plans
Change in retirement liabilities	26	10	52	20
Other comprehensive income/(loss)	2,694	(415)	3,851	(1,757)
Comprehensive income	$ 6,966	$ 5,696	$ 14,321	$ 10,159

Other comprehensive income (loss) derivatives net of tax period increase decrease.

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount after tax, before reclassification adjustments, of unrealized holding gain (loss) on available-for-sale securities and unrealized holding gain (loss) related to transfers of securities into the available-for-sale classification and out of the held-to-maturity classification.

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Amount after tax and reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities. Excludes amounts related to other than temporary impairment (OTTI) loss.

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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Amount after tax of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities.

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