Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	$ (7,418)	$ 3,371
Change in Other comprehensive income before reclassification, Unrealized gains and Losses on available-for-sale Securities	(7,699)	3,189
Amount reclassified from accumalted other comperhensive income, unrealized gain and losses and available for sale securities	281	182
Net Current period other comprehensive other income, Unrealized gains and Losses on available-for-sale Securities	(9,784)	3,371
TOTAL Balance	(14,704)	(14,164)
TOTAL Balance	(24,488)	(10,793)
Accumulated Net Unrealized Investment Gain (Loss) [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	(7,201)	3,188
Change in Other comprehensive income before reclassification, Unrealized gains and Losses on available-for-sale Securities	(7,699)	3,189
Amount reclassified from accumalted other comperhensive income, unrealized gain and losses and available for sale securities	0	(1)
Net Current period other comprehensive other income, Unrealized gains and Losses on available-for-sale Securities	(7,201)	3,188
TOTAL Balance	2,258	(1,077)
TOTAL Balance	(4,943)	2,111
Accumulated Defined Benefit Plans Adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	(2,583)	183
Change in Other comprehensive income before reclassification, Unrealized gains and Losses on available-for-sale Securities	0	0
Amount reclassified from accumalted other comperhensive income, unrealized gain and losses and available for sale securities	281	183
Net Current period other comprehensive other income, Unrealized gains and Losses on available-for-sale Securities	(2,583)	183
TOTAL Balance	(16,962)	(13,087)
TOTAL Balance	$ (19,545)	$ (12,904)