CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY (USD $) In Thousands, unless otherwise specified	Total	Total AAR Stockholders' Equity	Common Stock	Capital Surplus	Retained Earnings	Treasury Stock	Accumulated Other Comprehensive Income (Loss)	Noncontrolling Interest
Balance at May. 31, 2009	$ 696,734	$ 696,734	$ 44,201	$ 405,029	$ 374,659	$ (103,159)	$ (23,996)
Increase (Decrease) in Stockholders' Equity
Net income	43,202	44,628			44,628			(1,426)
Exercise of stock options and stock awards	4,020	4,020	217	4,753		(950)
Tax benefit related to share-based plans	817	817		817
Restricted stock activity	7,391	6,983	452	6,531				408
Bond hedge and warrant activity	(252)	(252)		86		(338)
Equity portion of bond repurchase	(374)	(374)		(374)
Foreign currency translation gain (loss), net of tax	(2,238)	(2,238)					(2,238)
Change in unrecognized pension and post retirement costs, net of tax	(3,412)	(3,412)					(3,412)
Assumption of noncontrolling interest	462							462
Balance at May. 31, 2010	746,350	746,906	44,870	416,842	419,287	(104,447)	(29,646)	(556)
Increase (Decrease) in Stockholders' Equity
Net income	69,826	69,826			69,826
Cash dividends	(2,983)	(2,983)			(2,983)
Exercise of stock options and stock awards	5,154	5,154	1	3,719		1,434
Tax benefit related to share-based plans	247	247		247
Restricted stock activity	8,156	8,156	115	2,783		5,258
Repurchase of shares	(2,539)	(2,539)				(2,539)
Bond hedge and warrant activity	(236)	(236)		(99)		(137)
Equity portion of bond repurchase	313	313		313
Foreign currency translation gain (loss), net of tax	3,290	3,290					3,290
Change in unrecognized pension and post retirement costs, net of tax	7,711	7,711					7,711
Balance at May. 31, 2011	835,289	835,845	44,986	423,805	486,130	(100,431)	(18,645)	(556)
Increase (Decrease) in Stockholders' Equity
Net income	68,029	67,723			67,723			306
Cash dividends	(12,081)	(12,081)			(12,081)
Exercise of stock options and stock awards	4,236	4,236		4,328		(92)
Tax benefit related to share-based plans	482	482		482
Restricted stock activity	8,851	8,851	(137)	(4,834)		13,822
Repurchase of shares	(3,659)	(3,659)				(3,659)
Bond hedge and warrant activity	(53)	(53)		(9)		(44)
Equity portion of bond repurchase	(150)	(150)		(150)
Unrealized loss on derivatives, net of tax	(3,887)	(3,887)					(3,887)
Foreign currency translation gain (loss), net of tax	(18,474)	(18,474)					(18,474)
Change in unrecognized pension and post retirement costs, net of tax	(14,184)	(14,184)					(14,184)
Assumption of noncontrolling interest	1,623							1,623
Balance at May. 31, 2012	$ 866,022	$ 864,649	$ 44,849	$ 423,622	$ 541,772	$ (90,404)	$ (55,190)	$ 1,373