Other Comprehensive Income Details 2 (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax	$ (3,590)	$ (3,462)	$ (3,905)	$ (2,640)
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Tax	(275)	(252)	(319)	(112)
Other Comprehensive Income (Loss), Reclassification Adjustment on Derivatives Included in Net Income, Net of Tax	(3,315)	(3,210)	(3,586)	(2,528)
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Adjustment, before Tax, Portion Attributable to Parent	3,890	4,651	11,639	14,150
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Tax, Portion Attributable to Parent	874	1,064	2,618	3,313
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Adjustment, Net of Tax	3,016	3,587	9,021	10,837
Interest Rate Swap [Member]
Interest Rate Cash Flow Hedge Gain (Loss) Reclassified to Earnings, Net	31	97	(82)	531
Cross Currency Swap [Member]
Interest Rate Cash Flow Hedge Gain (Loss) Reclassified to Earnings, Net	(3,621)	$ (3,559)	(3,823)	$ (3,171)
Foreign Currency Transaction Gain (Loss), Unrealized	2,400		(300)
Interest Income, Other	$ 1,200		$ 3,500