Condensed Consolidated Statements of Comprehensive Income (USD $) In Millions, unless otherwise specified	3 Months Ended	9 Months Ended
Feb. 28, 2015	Feb. 28, 2014	Feb. 28, 2015	Feb. 28, 2014
Condensed Consolidated Statements of Comprehensive Income
Net income (loss) attributable to AAR and noncontrolling interest	$ (34.4)us-gaap_ProfitLoss	$ 18.0us-gaap_ProfitLoss	$ (4.7)us-gaap_ProfitLoss	$ 56.0us-gaap_ProfitLoss
Other comprehensive income (loss), net of tax expense (benefit):
Currency translation adjustments, net of tax of ($0.6) and $0.2 for the three months ended February 28, 2015 and 2014, respectively, and $0.6 and $0.8 for the nine months ended February 28, 2015 and 2014, respectively	(26.1)	4.2	(49.9)	16.0
Unrealized gain on derivative instruments:
Unrealized gain arising during period, net of tax of $0.1 and $0 for the three months ended February 28, 2015 and 2014, respectively, and $0.3 and $0.2 for the nine months ended February 28, 2015 and 2014, respectively	0.4	0.3	0.6	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 and $0.2 for the three months ended February 28, 2015 and 2014, respectively, and $0 and $0.5 for the nine months ended February 28, 2015 and 2014, respectively	(0.2)	0.2	(0.1)	0.7
Other comprehensive (loss) income, net of tax	(25.9)	4.7	(49.4)	17.3
Comprehensive (loss) income, net of tax	(60.3)	22.7	(54.1)	73.3
Comprehensive income related to noncontrolling interest	(0.1)	(0.1)	(0.2)	(0.2)
Comprehensive (loss) income attributable to AAR	$ (60.4)us-gaap_ComprehensiveIncomeNetOfTax	$ 22.6us-gaap_ComprehensiveIncomeNetOfTax	$ (54.3)us-gaap_ComprehensiveIncomeNetOfTax	$ 73.1us-gaap_ComprehensiveIncomeNetOfTax

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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