Changes in Accumulated Other Comprehensive Income Balances (Schedule of Accumulated Other Comprehensive Income (Loss)) (Details) - USD ($) $ in Thousands		12 Months Ended
	Jan. 01, 2018	Dec. 31, 2018	Dec. 31, 2017
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	$ 12,234	$ 12,234
Other comprehensive income (loss):
Change in net actuarial gain		(576)	$ 548
Tax effect on change in net actuarial gain		121	(192)
Unrealized holding gains arising during the period		(3,343)	9,117
Tax effect on unrealized gains arising during the period		702	(3,191)
Reclassification adjustment for gains included in net realized gains		(1,803)	(6,799)
Tax effect on reclassification adjustment for gains included in income tax expense		379	2,380
Other comprehensive (loss) income, net of tax		(4,520)	1,863
Reclassification of certain tax effects from accumulated other comprehensive income at January 1,2018	2,600
Ending Balance		(6,660)	12,234
Pension Liability [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	(2,310)	(2,310)	(2,666)
Other comprehensive income (loss):
Change in net actuarial gain		(576)	548
Tax effect on change in net actuarial gain		121	(192)
Other comprehensive (loss) income, net of tax		(455)	356
Reclassification of certain tax effects from accumulated other comprehensive income at January 1,2018		(569)
Ending Balance		(3,334)	(2,310)
Unrealized Gains (Loss) [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	14,544	14,544	13,037
Other comprehensive income (loss):
Unrealized holding gains arising during the period		(3,343)	9,117
Tax effect on unrealized gains arising during the period		702	(3,191)
Reclassification adjustment for gains included in net realized gains		(1,803)	(6,799)
Tax effect on reclassification adjustment for gains included in income tax expense		379	2,380
Other comprehensive (loss) income, net of tax		(4,065)	1,507
Reclassification of certain tax effects from accumulated other comprehensive income at January 1,2018		3,188
Cumulative effect of adoption of updated accounting guindance for equity financial instruments at January 1, 2018		(16,993)
Ending Balance		(3,326)	14,544
Accumulated Other Comprehensive Income (Loss) [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	12,234	12,234	10,371
Other comprehensive income (loss):
Change in net actuarial gain		(576)	548
Tax effect on change in net actuarial gain		121	(192)
Unrealized holding gains arising during the period		(3,343)	9,117
Tax effect on unrealized gains arising during the period		702	(3,191)
Reclassification adjustment for gains included in net realized gains		(1,803)	(6,799)
Tax effect on reclassification adjustment for gains included in income tax expense		379	2,380
Other comprehensive (loss) income, net of tax		(4,520)	1,863
Reclassification of certain tax effects from accumulated other comprehensive income at January 1,2018		2,619
Cumulative effect of adoption of updated accounting guindance for equity financial instruments at January 1, 2018		(16,993)
Ending Balance		(6,660)	12,234
Parent Company [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	$ 12,234	12,234
Other comprehensive income (loss):
Ending Balance		$ (6,660)	$ 12,234