Accumulated Other Comprehensive Loss (Accumulated Other Comprehensive Loss) (Details) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Aug. 31, 2019	May 31, 2019	Aug. 31, 2018	May 31, 2018	Aug. 31, 2019	Aug. 31, 2018
Schedule of Accumulated Other Comprehensive Loss [Line Items]
Beginning balance		$ (68,010)			$ (68,010)
Other comprehensive loss before reclassifications					(24,554)
Amounts reclassified from accumulated other comprehensive loss					934
Other comprehensive income (loss), net of taxes	$ (10,424)	(13,196)	$ 610	$ (733)	(23,620)	$ (123)
Ending balance	(91,630)				(91,630)
Net Unrecognized Actuarial Losses
Schedule of Accumulated Other Comprehensive Loss [Line Items]
Beginning balance		(70,478)			(70,478)
Other comprehensive loss before reclassifications					0
Amounts reclassified from accumulated other comprehensive loss					711
Other comprehensive income (loss), net of taxes					711
Ending balance	(69,767)				(69,767)
Net Unrecognized Hedge Gains (Losses)
Schedule of Accumulated Other Comprehensive Loss [Line Items]
Beginning balance		$ 2,468			2,468
Other comprehensive loss before reclassifications					(24,554)
Amounts reclassified from accumulated other comprehensive loss					223
Other comprehensive income (loss), net of taxes					(24,331)
Ending balance	$ (21,863)				$ (21,863)