CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Millions, unless otherwise specified	12 Months Ended
	May 31, 2014	May 31, 2013	May 31, 2012
Cash flows provided from operating activities:
Net income attributable to AAR and noncontrolling interest	$ 73.2	$ 55.5	$ 68.0
Adjustments to reconcile net income attributable to AAR and noncontrolling interest to net cash provided from operating activities:
Depreciation and amortization	80.4	79.7	72.0
Amortization of stock-based compensation	8.7	11.1	12.5
Amortization of debt discount	5.3	9.6	13.2
Amortization of overhaul costs	33.0	28.9	8.3
Deferred tax provision	9.6	29.5	32.8
Restructuring and impairment charges			3.7
Loss on extinguishment of debt		0.3	0.7
Earnings from joint ventures	(3.1)	(6.8)	(1.5)
Changes in certain assets and liabilities, net of acquisitions:
Accounts receivable	16.7	6.0	36.3
Inventories	(47.9)	16.1	(47.6)
Rotable spares and equipment on or available for short-term lease	11.3	10.4	5.6
Equipment on or available for long-term lease	(41.7)	0.8	16.5
Accounts and trade notes payable	20.1	(50.7)	18.3
Accrued and other liabilities	4.3	11.8	(20.9)
Other, primarily program and overhaul costs	(30.1)	(39.3)	(123.7)
Net cash provided from operating activities	139.8	162.9	94.2
Cash flows used in investing activities:
Property, plant and equipment expenditures	(26.5)	(37.6)	(91.2)
Proceeds from disposal of assets	2.0	11.8	4.1
Payments for acquisitions	(15.3)	(21.3)	(298.1)
Proceeds from aircraft joint ventures	(0.2)	15.4	1.6
Other	(0.9)	(1.1)	(6.6)
Net cash used in investing activities	(40.9)	(32.8)	(390.2)
Cash flows (used in) provided from financing activities:
Short-term borrowings (repayments), net	10.0	(160.0)	180.0
Proceeds from borrowings		181.8	236.8
Reduction in borrowing	(88.9)	(114.3)	(83.5)
Reduction in equity due to convertible bond repurchase		(0.5)	(1.2)
Cash dividends	(11.8)	(12.8)	(12.1)
Purchase of treasury stock	(1.0)	(14.6)	(3.7)
Stock option exercises	5.1	1.1	3.0
Other	0.7	(4.4)	(12.5)
Net cash (used in) provided from financing activities	(85.9)	(123.7)	306.8
Effect of exchange rate changes on cash	0.9	1.2	(0.5)
Increase in cash and cash equivalents	13.9	7.6	10.3
Cash and cash equivalents, beginning of year	75.3	67.7	57.4
Cash and cash equivalents, end of year	$ 89.2	$ 75.3	$ 67.7