Condensed Consolidated Statements of Comprehensive Income (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Feb. 28, 2014	Feb. 28, 2013	Feb. 28, 2014	Feb. 28, 2013
Condensed Consolidated Statements of Comprehensive Income
Net income attributable to AAR and noncontrolling interest	$ 18.0	$ 18.5	$ 56.0	$ 54.7
Other comprehensive income (loss), net of tax:
Currency translation adjustments, net of tax of $0.2 and $0.1 for the three months ended February 28, 2014 and 2013, respectively, and $0.8 and $0.1 for the nine months ended February 28, 2014 and 2013, respectively	4.2	0.7	16.0	13.0
Unrealized gain (loss) on derivative instruments:
Unrealized gain (loss) arising during period, net of tax of $0 and $0 for the three months ended February 28, 2014 and 2013, respectively, and $0.2 and $0 for the nine months ended February 28, 2014 and 2013, respectively	0.3	0.4	0.6
Pension and other post-retirement plans:
Amortization of actuarial loss and prior service cost included in net income, net of tax of $0.2 and $0 for the three months ended February 28, 2014 and 2013, respectively, and $0.5 and $0 for the nine months ended February 28, 2014 and 2013, respectively	0.2		0.7
Other comprehensive income, net of tax	22.7	19.6	73.3	67.7
Comprehensive income related to noncontrolling interest	(0.1)	(0.1)	(0.2)	(0.3)
Comprehensive income attributable to AAR	$ 22.6	$ 19.5	$ 73.1	$ 67.4