Stockholders' Equity (Accumulated Other Comprehensive (Loss) Income) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Accumulated Other Comprehensive (Loss) Income [Roll Forward]
Unrealized Gain on Securities	$ 5,300
Realized gain on sale of securities, net of tax	252
Other comprehensive income (loss), net of reclassifications and tax	17,592
Unrealized Gain on Securities	22,640
Unrecognized Net Pension and Postretirement Costs	(3,958)
Other comprehensive income (loss), net of reclassifications and tax	(267)
Unrecognized Net Pension and Postretirement Costs	(3,934)
Unrealized Loss on Cash Flow Hedge	(2,767)
Other comprehensive income (loss), net of reclassifications and tax	(7,687)	$ (1,448)
Unrealized Loss on Cash Flow Hedge	(10,454)
Accumulated Other Comprehensive Income (Loss)	(1,425)
Accumulated Other Comprehensive Income (Loss)	8,252
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	9,638
Other Comprehensive Income (Loss), Defined Benefit Plan, Settlement and Curtailment Gain (Loss), after Tax	$ 291