CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY - USD ($) $ in Millions	Total AAR Stockholders' Equity	Common Stock	Capital Surplus	Retained Earnings	Treasury Stock	Accumulated Other Comprehensive Income (Loss)	Noncontrolling Interest	Total
Balance at May. 31, 2012	$ 864.6	$ 44.8	$ 423.6	$ 541.8	$ (90.4)	$ (55.2)	$ 1.4	$ 866.0
Increase (Decrease) in Stockholders' Equity
Net income	55.0			55.0			0.5	55.5
Cash dividends	(11.9)			(11.9)			(1.0)	(12.9)
Stock option activity	4.5		2.8		1.7			4.5
Restricted stock activity	7.8	(0.1)	4.7		3.2			7.8
Repurchase of shares	(14.6)				(14.6)			(14.6)
Equity portion of bond repurchase	0.5		0.5					0.5
Other comprehensive (loss) income, net of tax	12.7					12.7		12.7
Balance at May. 31, 2013	918.6	44.7	431.6	584.9	(100.1)	(42.5)	0.9	919.5
Increase (Decrease) in Stockholders' Equity
Net income	72.9			72.9			0.3	73.2
Cash dividends	(11.8)			(11.8)				(11.8)
Stock option activity	7.8		2.8		5.0			7.8
Restricted stock activity	(0.2)		2.0		(2.2)			(0.2)
Repurchase of shares	(1.0)				(1.0)			(1.0)
Other comprehensive (loss) income, net of tax	13.2					13.2		13.2
Balance at May. 31, 2014	999.5	44.7	436.4	646.0	(98.3)	(29.3)	1.2	1,000.7
Increase (Decrease) in Stockholders' Equity
Net income	10.2			10.2			0.2	10.4
Cash dividends	(11.9)			(11.9)			(0.6)	(12.5)
Stock option activity	6.3		2.1		4.2			6.3
Restricted stock activity	4.2	0.2	4.7		(0.7)			4.2
Repurchase of shares	(151.5)				(151.5)			(151.5)
Other	0.6		0.6				$ 0.8	1.4
Other comprehensive (loss) income, net of tax	(11.1)					(11.1)		(11.1)
Balance at May. 31, 2015	$ 845.1	$ 44.9	$ 442.6	$ 644.3	$ (246.3)	$ (40.4)		$ 845.1