Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance beginning	$ 228,048	$ 218,985
Before reclassifications	2,658	2,475
Reclassifications	(175)	14
Balance ending	233,478	224,018
Total [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance beginning	673
Balance ending	3,156	(2,230)
Unrealized Gains and Losses on Available-for-Sale Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Before reclassifications	2,658	2,475
Reclassifications	(175)	14
Balance ending	3,340
Changes in Pension Plan Assets and Benefit Obligations [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Before reclassifications	0	0
Reclassifications	0	0
Balance ending	(184)
Calculated under Revenue Guidance in Effect before Topic 606 [Member] | Total [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance beginning	673	(4,719)
Balance ending		(2,230)
Calculated under Revenue Guidance in Effect before Topic 606 [Member] | Unrealized Gains and Losses on Available-for-Sale Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance beginning	857	(4,631)
Balance ending		(2,142)
Calculated under Revenue Guidance in Effect before Topic 606 [Member] | Changes in Pension Plan Assets and Benefit Obligations [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance beginning	$ (184)	(88)
Balance ending		$ (88)