Condensed Consolidated Statements of Cash Flows (USD $) In Millions, unless otherwise specified	3 Months Ended
	Aug. 31, 2012	Aug. 31, 2011
Cash flows from operating activities:
Net income attributable to AAR and noncontrolling interest	$ 18.3	$ 16.6
Adjustments to reconcile net income attributable to AAR and noncontrolling interest to net cash provided from operating activities:
Depreciation and amortization	20.3	15.8
Amortization of stock-based compensation	2.9	2.6
Amortization of debt discount	2.9	3.2
Amortization of overhaul costs	5.9	0.9
Deferred tax provision	5.6	2.8
Tax benefits from exercise of stock options		(0.8)
Loss on extinguishment of debt	0.2
Earnings from joint ventures	(1.4)	(0.2)
Changes in certain assets and liabilities:
Accounts and notes receivable	20.7	(9.0)
Inventories	(4.3)	(36.8)
Rotable spares and equipment on or available for short-term lease	(1.5)	(8.3)
Equipment on long-term lease	1.3	19.5
Accounts and trade notes payable	(25.6)	5.0
Accrued and other liabilities	(3.4)	(5.1)
Other, primarily program and overhaul costs	(8.7)	(31.8)
Net cash provided from (used in) operating activities	33.2	(25.6)
Cash flows from investing activities:
Property, plant and equipment expenditures	(11.0)	(41.8)
Proceeds from sale of equipment	11.0
Payments for acquisitions	(16.5)
Other	(0.4)	(0.5)
Net cash used in investing activities	(16.9)	(42.3)
Cash flows from financing activities:
Proceeds from borrowing	20.0	50.0
Reduction in borrowing, net	(27.6)	(3.1)
Reduction in capital lease obligations		(0.5)
Reduction in equity due to convertible bond repurchases	(0.3)
Cash dividends	(3.0)	(3.0)
Purchase of treasury stock	(6.1)	(1.0)
Stock option exercises		2.9
Tax benefits from exercise of stock options		0.8
Net cash (used in) provided from financing activities	(17.0)	46.1
Effect of exchange rate changes on cash	0.7	(0.1)
Decrease in cash and cash equivalents		(21.9)
Cash and cash equivalents, beginning of period	67.7	57.4
Cash and cash equivalents, end of period	$ 67.7	$ 35.5