Accumulated Other Comprehensive Income (Details 2) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Net securities gains (losses)	$ 194	$ (4)
Income tax expense	(3,020)	(2,217)
Unrealized gain (loss) on securities, net of tax	12,181	9,682
Change in funded status of post retirement benefits	404	303
Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Unrealized gain (loss) on securities, net of tax	(258)	(306)
Accumulated Net Unrealized Investment Gain (Loss) [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Net securities gains (losses)	194	(4)
Income tax expense	(48)	1
Unrealized gain (loss) on securities, net of tax	146	(3)
Accumulated Defined Benefit Plans Adjustment [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Income tax expense	88	86
Unrealized gain (loss) on securities, net of tax	(404)	(303)
Change in funded status of post retirement benefits	$ (492)	$ (389)