Accumulated Other Comprehensive Loss (Accumulated Other Comprehensive Loss) (Details) - USD ($) $ in Thousands	3 Months Ended						9 Months Ended
	Nov. 30, 2021	Aug. 31, 2021	May 31, 2021	Nov. 30, 2020	Aug. 31, 2020	May 31, 2020	Nov. 30, 2021	Nov. 30, 2020
Schedule of Accumulated Other Comprehensive Loss [Line Items]
Beginning balance			$ (118,691)				$ (118,691)
Other comprehensive income before reclassifications							6,386
Amounts reclassified from accumulated other comprehensive loss							12,004
Other comprehensive income (loss), net of taxes	$ 12,042	$ 3,411	2,937	$ 7,502	$ 4,979	$ (15,334)	18,390	$ (2,853)
Ending balance	(100,301)						(100,301)
Net Unrecognized Actuarial Losses
Schedule of Accumulated Other Comprehensive Loss [Line Items]
Beginning balance			(92,662)				(92,662)
Other comprehensive income before reclassifications							0
Amounts reclassified from accumulated other comprehensive loss							1,976
Other comprehensive income (loss), net of taxes							1,976
Ending balance	(90,686)						(90,686)
Net Unrecognized Hedge Gains (Losses)
Schedule of Accumulated Other Comprehensive Loss [Line Items]
Beginning balance			$ (26,029)				(26,029)
Other comprehensive income before reclassifications							6,386
Amounts reclassified from accumulated other comprehensive loss							10,028
Other comprehensive income (loss), net of taxes							16,414
Ending balance	$ (9,615)						$ (9,615)