Condensed Consolidated Statements of Comprehensive Income (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Nov. 30, 2013	Nov. 30, 2012	Nov. 30, 2013	Nov. 30, 2012
Condensed Consolidated Statements of Comprehensive Income
Net income attributable to AAR and noncontrolling interest	$ 20.0	$ 17.9	$ 38.0	$ 36.2
Other comprehensive income (loss), net of tax:
Currency translation adjustments, net of tax of $0.4 and $0 for the three months ended November 30, 2013 and 2012, respectively, and $0.6 and $0 for the six months ended November 30, 2013 and 2012, respectively	9.0	8.0	11.8	12.3
Unrealized gain (loss) on derivative instruments:
Unrealized gain (loss) arising during period, net of tax of ($0.2) and $0 for the three months ended November 30, 2013 and 2012, respectively, and $0.2 and ($0.2) for the six months ended November 30, 2013 and 2012, respectively	(0.6)		0.3	(0.4)
Pension and other post-retirement plans:
Amortization of actuarial loss and prior service cost included in net income, net of tax of $0.1 and $0 for the three months ended November 30, 2013 and 2012, respectively, and $0.3 and $0 for the six months ended November 30, 2013 and 2012, respectively	0.3		0.5
Other comprehensive income, net of tax	28.7	25.9	50.6	48.1
Comprehensive income related to noncontrolling interest		(0.1)	(0.1)	(0.2)
Comprehensive income attributable to AAR	$ 28.7	$ 25.8	$ 50.5	$ 47.9