Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Millions	12 Months Ended
	May 31, 2016	May 31, 2015	May 31, 2014
Accumulated Other Comprehensive Loss
Accumulated Other Comprehensive Income (Loss), Net of Tax, Beginning Balance	$ (40.4)	$ (29.3)	$ (42.5)
Other comprehensive income (loss) before reclassifications	(5.6)	(64.2)	11.9
Amounts reclassified from AOCL	1.6	3.4	1.3
Total other comprehensive income (loss), net of tax	(4.0)	(11.1)	13.2
Accumulated Other Comprehensive Income (Loss), Net of Tax, Ending Balance	(44.4)	(40.4)	(29.3)
Telair Cargo Group
Accumulated Other Comprehensive Loss
Sale of business		49.7
Currency Translation Adjustments
Accumulated Other Comprehensive Loss
Accumulated Other Comprehensive Income (Loss), Net of Tax, Beginning Balance	0.9	8.7	(5.3)
Reclassification within AOCL	(2.0)
Other comprehensive income (loss) before reclassifications		(56.9)	14.0
Total other comprehensive income (loss), net of tax		(7.8)	14.0
Accumulated Other Comprehensive Income (Loss), Net of Tax, Ending Balance	(1.1)	0.9	8.7
Currency Translation Adjustments | Telair Cargo Group
Accumulated Other Comprehensive Loss
Sale of business		49.1
Pensions Plans
Accumulated Other Comprehensive Loss
Accumulated Other Comprehensive Income (Loss), Net of Tax, Beginning Balance	(41.3)	(35.4)	(33.9)
Reclassification within AOCL	2.0
Other comprehensive income (loss) before reclassifications	(5.6)	(7.9)	(2.8)
Amounts reclassified from AOCL	1.6	1.4	1.3
Total other comprehensive income (loss), net of tax	(4.0)	(5.9)	(1.5)
Accumulated Other Comprehensive Income (Loss), Net of Tax, Ending Balance	$ (43.3)	(41.3)	(35.4)
Pensions Plans | Telair Cargo Group
Accumulated Other Comprehensive Loss
Sale of business		0.6
Derivative Instruments
Accumulated Other Comprehensive Loss
Accumulated Other Comprehensive Income (Loss), Net of Tax, Beginning Balance		(2.6)	(3.3)
Other comprehensive income (loss) before reclassifications		0.6	0.7
Amounts reclassified from AOCL		2.0
Total other comprehensive income (loss), net of tax		$ 2.6	0.7
Accumulated Other Comprehensive Income (Loss), Net of Tax, Ending Balance			$ (2.6)