Comprehensive Income/Loss (Comprised of the following Components) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance			$ 18,169	$ (1,173)
Net change in other comprehensive income (loss)	$ 2,117	$ 14,075	33,676	22,129
Ending Balance	51,845	20,956	51,845	20,956
Unrealized Gain (Loss) on Securities
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance			4,398	(5,947)
Net change in other comprehensive income (loss)			11,042	10,174
Ending Balance	15,440	4,227	15,440	4,227
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance			16,479	6,148
Net change in other comprehensive income (loss)			23,181	11,875
Ending Balance	39,660	18,023	39,660	18,023
Defined Benefit Postretirement Plans
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance			(2,708)	(1,374)
Net change in other comprehensive income (loss)			(547)	80
Ending Balance	(3,255)	(1,294)	(3,255)	(1,294)
AOCI Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Net change in other comprehensive income (loss)	$ 2,117	$ 14,075	$ 33,676	$ 22,129