AAR (AIR) 10-Q 20 Dec 13 2014 Q2 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	6 Months Ended
	Nov. 30, 2013
Document and Entity Information	'
Entity Registrant Name	'AAR CORP
Entity Central Index Key	'0000001750
Document Type	'10-Q
Document Period End Date	30-Nov-13
Amendment Flag	'false
Current Fiscal Year End Date	'--05-31
Entity Current Reporting Status	'Yes
Entity Filer Category	'Large Accelerated Filer
Entity Common Stock, Shares Outstanding	39,600,386
Document Fiscal Year Focus	'2014
Document Fiscal Period Focus	'Q2

Condensed_Consolidated_Balance

Condensed Consolidated Balance Sheets (USD $)	Nov. 30, 2013	31-May-13
In Millions, unless otherwise specified
Current assets:	'	'
Cash	$98.50	$75.30
Accounts receivable, less allowances of $8.1 and $8.7, respectively	319.8	297.4
Inventories	463.8	453.7
Rotable spares and equipment on or available for short-term lease	122.7	129.2
Deposits, prepaids and other	59.7	60.1
Deferred tax assets	18	18
Total current assets	1,082.50	1,033.70
Property, plant and equipment, net of accumulated depreciation of $396.7 and $354.5, respectively	344.4	361.7
Other assets:	'	'
Goodwill	260.7	255.6
Intangible assets, net of accumulated amortization of $30.9 and $25.1, respectively	159.2	157.8
Equipment on long-term lease	61.9	64.7
Capitalized program development costs	111.2	124.9
Investment in joint ventures	31.1	31.8
Other	104.9	106.7
Total other assets	729	741.5
Total assets	2,155.90	2,136.90
Current liabilities:	'	'
Current maturities of long-term debt	87.3	86.4
Accounts payable	144.5	149.3
Accrued liabilities	141.1	153.3
Total current liabilities	372.9	389
Long-term debt, less current maturities	593.5	622.2
Deferred tax liabilities	153.5	138.2
Other liabilities and deferred income	68.8	68
Total noncurrent liabilities	815.8	828.4
Equity:	'	'
Preferred stock, $1.00 par value, authorized 250,000 shares; none issued	'	'
Common stock, $1.00 par value, authorized 100,000,000 shares; issued 44,681,304 and 44,691,437 shares at cost, respectively	44.7	44.7
Capital surplus	431.6	431.6
Retained earnings	616.8	584.9
Treasury stock, 5,080,918 and 5,309,252 shares at cost, respectively	-97	-100.1
Accumulated other comprehensive loss	-29.9	-42.5
Total AAR stockholders' equity	966.2	918.6
Noncontrolling interest	1	0.9
Total equity	967.2	919.5
Total liabilities and equity	$2,155.90	$2,136.90

Condensed_Consolidated_Balance1

Condensed Consolidated Balance Sheets (Parenthetical) (USD $)	Nov. 30, 2013	31-May-13
In Millions, except Share data, unless otherwise specified
Condensed Consolidated Balance Sheets	'	'
Accounts receivable, allowances (in dollars)	$8.10	$8.70
Property, plant and equipment, accumulated depreciation (in dollars)	396.7	354.5
Intangible assets, accumulated amortization (in dollars)	$30.90	$25.10
Preferred stock, par value (in dollars per share)	$1	$1
Preferred stock, authorized shares	250,000	250,000
Preferred stock, issued shares	0	0
Common stock, par value (in dollars per share)	$1	$1
Common stock, authorized shares	100,000,000	100,000,000
Common stock, issued shares	44,681,304	44,691,437
Treasury stock, shares	5,080,918	5,309,252

Condensed_Consolidated_Stateme

Condensed Consolidated Statements of Income (USD $)	3 Months Ended		6 Months Ended
In Millions, except Per Share data, unless otherwise specified	Nov. 30, 2013	Nov. 30, 2012	Nov. 30, 2013	Nov. 30, 2012
Sales:	'	'	'	'
Sales from products	$328.90	$291.80	$634.40	$619.30
Sales from services	211.8	221	420.8	444
Total sales	540.7	512.8	1,055.20	1,063.30
Cost and operating expenses:	'	'	'	'
Cost of products	286	255.4	555	539.5
Cost of services	163.7	170	324.5	346.1
Selling, general and administrative	51.1	50.8	98.8	104.1
Total costs and operating expenses	500.8	476.2	978.3	989.7
Earnings from joint ventures	0.8	1.2	2	2.6
Operating income	40.7	37.8	78.9	76.2
Loss on extinguishment of debt	'	-0.1	'	-0.3
Interest expense	-10.5	-10.8	-21.5	-21.4
Interest income	0.3	0.3	0.6	0.7
Income before provision for income taxes	30.5	27.2	58	55.2
Provision for income taxes	10.5	9.3	20	19
Net income attributable to AAR and noncontrolling interest	20	17.9	38	36.2
Income attributable to noncontrolling interest	'	-0.1	-0.1	-0.2
Net income attributable to AAR	$20	$17.80	$37.90	$36
Earnings per share - basic (in dollars per share)	$0.51	$0.45	$0.96	$0.90
Earnings per share - diluted (in dollars per share)	$0.50	$0.44	$0.95	$0.89

Condensed_Consolidated_Stateme1

Condensed Consolidated Statements of Comprehensive Income (USD $)	3 Months Ended		6 Months Ended
In Millions, unless otherwise specified	Nov. 30, 2013	Nov. 30, 2012	Nov. 30, 2013	Nov. 30, 2012
Condensed Consolidated Statements of Comprehensive Income	'	'	'	'
Net income attributable to AAR and noncontrolling interest	$20	$17.90	$38	$36.20
Other comprehensive income (loss), net of tax:	'	'	'	'
Currency translation adjustments, net of tax of $0.4 and $0 for the three months ended November 30, 2013 and 2012, respectively, and $0.6 and $0 for the six months ended November 30, 2013 and 2012, respectively	9	8	11.8	12.3
Unrealized gain (loss) on derivative instruments:	'	'	'	'
Unrealized gain (loss) arising during period, net of tax of ($0.2) and $0 for the three months ended November 30, 2013 and 2012, respectively, and $0.2 and ($0.2) for the six months ended November 30, 2013 and 2012, respectively	-0.6	'	0.3	-0.4
Pension and other post-retirement plans:	'	'	'	'
Amortization of actuarial loss and prior service cost included in net income, net of tax of $0.1 and $0 for the three months ended November 30, 2013 and 2012, respectively, and $0.3 and $0 for the six months ended November 30, 2013 and 2012, respectively	0.3	'	0.5	'
Other comprehensive income, net of tax	28.7	25.9	50.6	48.1
Comprehensive income related to noncontrolling interest	'	-0.1	-0.1	-0.2
Comprehensive income attributable to AAR	$28.70	$25.80	$50.50	$47.90

Condensed_Consolidated_Stateme2

Condensed Consolidated Statements of Comprehensive Income (Parenthetical) (USD $)	3 Months Ended		6 Months Ended
In Millions, unless otherwise specified	Nov. 30, 2013	Nov. 30, 2012	Nov. 30, 2013	Nov. 30, 2012
Condensed Consolidated Statements of Comprehensive Income	'	'	'	'
Currency translation adjustments, tax	$0.40	$0	$0.60	$0
Unrealized gain (loss) arising during period, tax	-0.2	0	0.2	-0.2
Amortization of actuarial loss and prior service cost included in net income, tax	$0.10	$0	$0.30	$0

Condensed_Consolidated_Stateme3

Condensed Consolidated Statements of Cash Flows (USD $)	6 Months Ended
In Millions, unless otherwise specified	Nov. 30, 2013	Nov. 30, 2012
Cash flows from operating activities:	'	'
Net income attributable to AAR and noncontrolling interest	$38	$36.20
Adjustments to reconcile net income attributable to AAR and noncontrolling interest to net cash provided from operating activities:	'	'
Depreciation and amortization	39.2	40.6
Amortization of stock-based compensation	4	4.8
Amortization of debt discount	3	5.7
Amortization of overhaul costs	17.5	12.7
Deferred tax provision	9.1	9.7
Earnings from joint ventures	-2	-2.6
Changes in certain assets and liabilities:	'	'
Accounts and notes receivable	-20.8	19.2
Inventories	-4.5	-20.8
Rotable spares and equipment on or available for short-term lease	7.3	5.1
Equipment on long-term lease	-1.5	1.3
Accounts payable	-5.9	-28.9
Accrued and other liabilities	-15.6	2.2
Other, primarily program and overhaul costs	-1.5	-24.9
Net cash provided from operating activities	66.3	60.3
Cash flows from investing activities:	'	'
Property, plant and equipment expenditures	-14.3	-19.1
Proceeds from sale of equipment	1.4	11.5
Payments for acquisitions	'	-16.5
Other	-0.6	-0.7
Net cash used in investing activities	-13.5	-24.8
Cash flows from financing activities:	'	'
Proceeds from borrowings	'	20
Reduction in borrowings	-30.4	-39.3
Reduction in equity due to convertible bond repurchases	'	-0.5
Cash dividends	-6	-7.1
Purchase of treasury stock	'	-8.5
Stock option exercises	5.2	'
Tax benefits from exercise of stock options	1	'
Other	-0.1	0.1
Net cash used in financing activities	-30.3	-35.3
Effect of exchange rate changes on cash	0.7	1.3
Increase in cash and cash equivalents	23.2	1.5
Cash and cash equivalents, beginning of period	75.3	67.7
Cash and cash equivalents, end of period	$98.50	$69.20

Condensed_Consolidated_Stateme4

Condensed Consolidated Statement of Changes in Equity (USD $)	Total	Total AAR Stockholders' Equity	Common Stock	Capital Surplus	Retained Earnings	Treasury Stock	Accumulated Other Comprehensive Income (Loss)	Noncontrolling Interest
In Millions, unless otherwise specified
Balance at May. 31, 2013	$919.50	$918.60	$44.70	$431.60	$584.90	($100.10)	($42.50)	$0.90
Increase (Decrease) in Stockholders' Equity	'	'	'	'	'	'	'	'
Net income	38	37.9	'	'	37.9	'	'	0.1
Cash dividends	-6	-6	'	'	-6	'	'	'
Stock option activity	5.6	5.6	'	0.6	'	5	'	'
Restricted stock activity	-2.5	-2.5	'	-0.6	'	-1.9	'	'
Other comprehensive income, net of tax	12.6	12.6	'	'	'	'	12.6	'
Balance at Nov. 30, 2013	$967.20	$966.20	$44.70	$431.60	$616.80	($97)	($29.90)	$1

Basis_of_Presentation

Basis of Presentation	6 Months Ended
	Nov. 30, 2013
Basis of Presentation	'
Basis of Presentation	'
	Note 1 — Basis of Presentation
	AAR CORP. and its subsidiaries are referred to herein collectively as “AAR,” “Company,” “we,” “us,” and “our,” unless the context indicates otherwise.  The accompanying Condensed Consolidated Financial Statements include the accounts of AAR and its subsidiaries after elimination of intercompany accounts and transactions.
	We have prepared these statements without audit, pursuant to the rules and regulations of the United States Securities and Exchange Commission (“SEC”).  The Condensed Consolidated Balance Sheet as of May 31, 2013 has been derived from audited financial statements.  To prepare the financial statements in conformity with U.S. generally accepted accounting principles (“GAAP”), management has made a number of estimates and assumptions relating to the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities.  Actual results could differ from those estimates.  Certain information and note disclosures, normally included in comprehensive financial statements prepared in accordance with GAAP, have been condensed or omitted pursuant to such rules and regulations of the SEC.  These Condensed Consolidated Financial Statements should be read in conjunction with the Consolidated Financial Statements and notes thereto included in our latest annual report on Form 10-K.
	In the opinion of management, the condensed consolidated financial statements reflect all adjustments (which consist only of normal recurring adjustments) necessary to present fairly the condensed consolidated financial position of AAR CORP. and its subsidiaries as of November 30, 2013, the Condensed Consolidated Statements of Income and the Condensed Consolidated Statements of Comprehensive Income for the three- and six-month periods ended November 30, 2013 and 2012, the Condensed Consolidated Statements of Cash Flows for the six-month periods ended November 30, 2013 and 2012, and the Condensed Consolidated Statement of Changes in Equity for the six-month period ended November 30, 2013.  The results of operations for such interim periods are not necessarily indicative of the results for the full year.

Revenue_Recognition

Revenue Recognition	6 Months Ended
	Nov. 30, 2013
Revenue Recognition	'
Revenue Recognition	'
	Note 2 — Revenue Recognition
	Sales and related cost of sales for product sales are recognized upon shipment of the product to the customer.  Our standard terms and conditions provide that title passes to the customer when the product is shipped to the customer.  Sales of certain defense products are recognized upon customer acceptance, which includes transfer of title.  Under the majority of our expeditionary airlift services contracts, we are paid and record as revenue a fixed daily amount per aircraft for each day an aircraft is available to perform airlift services.  In addition, we are paid and record as revenue an amount which is based on number of hours flown.  Sales from services and the related cost of services are generally recognized when customer-owned material is shipped back to the customer.  We have adopted this accounting policy because at the time the customer-owned material is shipped back to the customer, all services related to that material are complete as our service agreements generally do not require us to provide services at customer sites.  Furthermore, serviced units are typically shipped to the customer immediately upon completion of the related services.  Sales and related cost of sales for certain long-term manufacturing contracts, certain large airframe maintenance contracts, and performance-based logistics programs are recognized by the percentage of completion method, either based on the relationship of costs incurred to date to the estimated total costs or the units of delivery method.  Lease revenues are recognized as earned.  Income from monthly or quarterly rental payments is recorded in the pertinent period according to the lease agreement.  However, for leases that provide variable rents, we recognize lease income on a straight-line basis.  In addition to a monthly lease rate, some engine leases require an additional rental amount based on the number of hours the engine is used in a particular month.  Lease income associated with these contingent rentals is recorded in the period in which actual usage is reported to us by the lessee, which is normally the month following the actual usage.
	Certain supply chain management programs we provide to our customers contain multiple elements or deliverables, such as program and warehouse management, parts distribution, and maintenance and repair services.  We recognize revenue for each element or deliverable that can be identified as a separate unit of accounting at the time of delivery based upon the relative fair value of the products and services.
	Included in accounts receivable as of November 30, 2013 and May 31, 2013, are $22.4 million and $28.4 million, respectively, of unbilled accounts receivable related to the KC10 supply agreement.  These unbilled accounts receivable relate to costs we have incurred on parts that were requested and accepted by our customer to support the program.  These costs have not been billed by us because the customer has not issued the final paperwork necessary to allow for billing.
	In addition to the unbilled accounts receivable, included in Other non-current assets on the Condensed Consolidated Balance Sheet as of November 30, 2013 and May 31, 2013, are $11.9 million and $9.9 million, respectively, of costs in excess of amounts billed for the flight-hour portion of the same KC10 supply agreement.  We expect to recover costs in excess of amounts billed through future billings and by identifying additional costs savings opportunities over the life of the program.

Accounting_for_StockBased_Comp

Accounting for Stock-Based Compensation	6 Months Ended
	Nov. 30, 2013
Accounting for Stock-Based Compensation	'
Accounting for Stock-Based Compensation	'
	Note 3 — Accounting for Stock-Based Compensation
	Stock Options
	In the first six months of fiscal 2014, as part of our annual long-term stock incentive compensation, we granted 1,027,515 stock options to eligible employees at an average exercise price of $25.43 and weighted average fair value of $10.24.  The fair value of stock options is estimated on the date of grant using the Black-Scholes option pricing model with the following assumptions:
		Six Months Ended
		November 30, 2013
	Risk-free interest rate	1.4	%
	Expected volatility of common stock	49.1	%
	Dividend yield	1.2	%
	Expected option term in years	5.2
	The total intrinsic value of stock options exercised during the six-month periods ended November 30, 2013 and 2012 was $3.7 million and $0.1, respectively.  Expense charged to operations for stock options was $1.0 and $0.9 million during the three months ended November 30, 2013 and 2012, respectively, and $1.5 and $1.6 million during the six months ended November 30, 2013 and 2012, respectively.
	Restricted Stock
	In the first six months of fiscal 2014, as part of our annual long-term stock incentive compensation, we granted 60,808 shares of performance-based restricted stock and 60,808 shares of time-based restricted stock to eligible employees.  The grant date fair value per share was $25.43.  In June 2013, we also granted 45,000 shares of time-based restricted stock to members of the Board of Directors with a grant date fair value per share of $20.68.  Expense charged to operations for restricted stock was $1.4 and $0.9 million during the three months ended November 30, 2013 and 2012, respectively, and $2.5 and $3.1 million during the six months ended November 30, 2013 and 2012, respectively.

Inventory

Inventory	6 Months Ended
	Nov. 30, 2013
Inventory	'
Inventory	'
	Note 4 — Inventory
	The summary of inventories is as follows:
		November 30,		May 31,
		2013		2013
	Raw materials and parts	$	103.5	$	83.9
	Work-in-process	74.6		84
	Purchased aircraft, parts, engines and components held for sale	285.7		285.8
		$	463.8	$	453.7

Supplemental_Cash_Flow_Informa

Supplemental Cash Flow Information	6 Months Ended
	Nov. 30, 2013
Supplemental Cash Flow Information	'
Supplemental Cash Flow Information	'
	Note 5 — Supplemental Cash Flow Information
		Six Months Ended
		November 30,
		2013		2012
	Interest paid	$	17	$	14.5
	Income taxes paid	5.6		12.9
	Income tax refunds received	6.5		5.6

Financing_Arrangements

Financing Arrangements	6 Months Ended
	Nov. 30, 2013
Financing Arrangements	'
Financing Arrangements	'
	Note 6 — Financing Arrangements
	A summary of the carrying amount of our debt is as follows:
		November 30,			May 31,
		2013			2013
	Revolving credit facility expiring April 24, 2018 with interest payable monthly	$	100		$	120
	Secured credit facility (secured by aircraft and related engines and components) due April 23, 2015 with floating interest rate, payable monthly	34.6			39.2
	Note payable due March 9, 2017 with floating interest rate, payable semi-annually on June 1 and December 1	35			40
	Notes payable due January 15, 2022 with interest at 7.25% payable semi-annually on January 15 and July 15	333			333.4
	Convertible notes payable due March 1, 2014 with interest at 1.625% payable semi-annually on March 1 and September 1	67.6			65.9
	Convertible notes payable due March 1, 2016 with interest at 2.25% payable semi-annually on March 1 and September 1	44.6			43.5
	Other(1)	66			66.6
	Total debt	680.8			708.6
	Current maturities of debt	(87.3		)	(86.4		)
	Long-term debt	$	593.5		$	622.2
	(1)         Included in Other at November 30, 2013 and May 31, 2013, respectively, is (i) a note payable due March 15, 2014 of $0.5 million and $1.2 million, (ii) a mortgage loan (secured by Wood Dale, Illinois facility) due August 1, 2015 of $11.0 million and $11.0 million, (iii) convertible notes due February 1, 2015 of $29.5 million and $29.4 million, and (iv) an industrial revenue bond (secured by property, plant, and equipment) due August 1, 2018 of $25.0 million and $25.0 million.
	During the six-month period ended November 30, 2012, we repurchased $6.4 million par value of our 1.625% convertible notes due March 1, 2014, $5.5 million par value of our 2.25% convertible notes due March 1, 2016 and $11.0 million par value of our 1.75% convertible notes due February 1, 2026.  The 1.625% notes, 2.25% notes and 1.75% notes were repurchased for $6.1 million, $4.9 million and $11.0 million cash, respectively, with a total loss of $0.3 million after consideration of unamortized discount and debt issuance costs.  The losses on the debt repurchases for the 1.625%, 2.25% and 1.75% convertible notes are recorded in Loss on extinguishment of debt on the Condensed Consolidated Statements of Income.
	At November 30, 2013, the face value of our debt was $679.3 million and the estimated fair value was approximately $705.8 million.
	The fair value amounts of our long-term debt securities are estimated using significant other observable inputs including quoted prices for similar assets or liabilities in active markets and quoted prices for identical or similar assets or liabilities in markets that are not active. The debt is classified as Level 2 in the fair value hierarchy.
	We are subject to a number of covenants under our financing arrangements, including restrictions which relate to the payment of cash dividends, maintenance of minimum net working capital levels, fixed charge coverage ratio, leverage ratio, sales of assets, additional financing, purchase of our shares and other matters.  We were in compliance with all covenants under our financing arrangements as of November 30, 2013.
	Convertible Notes
	As of November 30, 2013 and May 31, 2013, the long-term debt and equity component (recorded in capital surplus, net of income tax benefit) consisted of the following:
		November 30,			May 31,
		2013			2013
	Long-term debt:
	Principal amount	$	148.3		$	148.3
	Unamortized discount	(6.6		)	(9.5		)
	Net carrying amount	$	141.7		$	138.8
	Equity component, net of tax	$	75.3		$	75.3
	The discount on the liability component of long-term debt is being amortized using the effective interest method based on an effective rate of 6.82% for our 1.625% convertible notes, 5.00% for our 1.75% convertible notes; and 7.41% for our 2.25% convertible notes.  For our 1.625%, 1.75%, and 2.25% convertible notes, the discount is being amortized through their respective maturity dates of March 1, 2014, February 1, 2015, and March 1, 2016.
	As of November 30, 2013 and 2012, for each of our convertible note issuances, the “if converted” value does not exceed its principal amount.
	The interest expense associated with the convertible notes was as follows:
		Three Months Ended						Six Months Ended
		November 30,						November 30,
		2013			2012			2013		2012
	Coupon interest	$	0.9		$	1		$	1.7	$	2
	Amortization of deferred financing fees	0.1			0.1			0.2		0.3
	Amortization of discount	1.5			2.8			2.9		5.6
	Interest expense related to convertible notes	$	2.5		$	3.9		$	4.8	$	7.9

Derivative_Instruments_and_Hed

Derivative Instruments and Hedging Activities	6 Months Ended
	Nov. 30, 2013
Derivative Instruments and Hedging Activities	'
Derivative Instruments and Hedging Activities	'
	Note 7 — Derivative Instruments and Hedging Activities
	We are exposed to interest rate risk associated with fluctuations in interest rates on our variable rate debt.  We utilize two derivative financial instruments to manage our variable interest rate exposure over a medium- to long-term period.  We have a floating-to-fixed interest rate swap and an interest rate cap agreement, each hedging $50.0 million of notional principal interest under our revolving Credit Agreement.
	We do not hold or issue derivative instruments for trading purposes and are not a party to any instruments with leverage or prepayment features.  In connection with derivative financial instruments, there exists the risk of the inability of counterparties to meet the terms of their contracts.  We mitigate this risk by performing financial reviews before the contract is entered into, as well as on-going periodic evaluations.  We do not expect any significant losses from counterparty defaults.
	We classify the derivatives as assets or liabilities on the balance sheet.  Accounting for the change in fair value of the derivatives is a function of whether the instrument qualifies for, and has been designated as, a hedging relationship, and the type of hedging relationship.  As of November 30, 2013, all of our derivative instruments were classified as cash flow hedges.  The fair value of the interest rate swap and interest rate cap agreements represents the difference in the present values of cash flows calculated at the contracted interest rates and at current market interest rates at the end of the reporting period.
	We record the fair value of assets and liabilities in accordance with the hierarchy established by the authoritative guidance for fair value measurements.  The fair value of our interest rate derivatives are classified as Level 2, which refers to fair values estimated using significant other observable inputs including quoted prices for similar assets or liabilities in active markets and quoted prices for identical or similar assets or liabilities in markets that are not active.  The following table summarizes the classification and fair values of our interest rate derivative instruments reported in the Condensed Consolidated Balance Sheet at November 30, 2013 and the Consolidated Balance Sheet at May 31, 2013.
	Derivatives designated		November 30,			May 31,
	as hedging instruments	Balance Sheet Classification	2013			2013
	Interest rate cap	Long-term assets	$	0.1		$	0.1
	Interest rate swap	Long-term liabilities	(3.1		)	(3.6		)
	We include gains and losses on the derivative instruments in other comprehensive income.  We recognize the gains and losses on our derivative instruments as an adjustment to interest expense in the period the hedged interest payment affects earnings.  The impact of the interest rate swap and interest cap agreement on the Condensed Consolidated Statement of Comprehensive Income for the three-month periods ended November 30, 2013 and 2012 was an unrealized loss of $0.6 million and zero, respectively.  The impact of the interest rate swap and interest cap agreement on the Condensed Consolidated Statement of Comprehensive Income for the six-month periods ended November 30, 2013 and 2012 was an unrealized gain of $0.3 million and $0.4 million, respectively.  The unrealized gains and losses were recorded in accumulated other comprehensive income (loss).  We expect minimal gain or loss to be reclassified into earnings within the next 12 months.

Earnings_per_Share

Earnings per Share	6 Months Ended
	Nov. 30, 2013
Earnings per Share	'
Earnings per Share	'
	Note 8 — Earnings per Share
	The computation of basic earnings per share is based on the weighted average number of common shares outstanding during each period.  The computation of diluted earnings per share is based on the weighted average number of common shares outstanding during the period plus, when their effect is dilutive, incremental shares consisting of shares subject to stock options, shares issuable upon vesting of restricted stock awards, and shares to be issued upon conversion of convertible debt.
	We used the “if-converted” method in calculating the diluted earnings per share effect of the assumed conversion of our contingently convertible debt issued in fiscal 2006 because the principal for that issuance can be settled in stock, cash, or a combination thereof.  Under the “if converted” method, the after-tax effect of interest expense related to the convertible securities is added back to net income, and the convertible debt is assumed to have been converted into common shares at the beginning of the period.
	In accordance with ASC 260-10-45, Share-Based Payment Arrangements and Participating Securities and the Two-Class Method, our unvested time-based restricted stock awards are deemed participating securities since these shares are entitled to participate in dividends declared on shares of common stock.  During periods of net income, the calculation of earnings per share for common stock excludes income attributable to unvested restricted stock awards from the numerator and excludes the dilutive impact of those shares from the denominator.  During periods of net loss, no effect is given to the participating securities because they do not share in the losses of the Company.
	The following table provides a reconciliation of the computations of basic and diluted earnings per share information for the three- and six-month periods ended November 30, 2013 and 2012.
		Three Months Ended						Six Months Ended
		November 30,						November 30,
		2013			2012			2013			2012
	Basic EPS:
	Net income attributable to AAR and noncontrolling interest	$	20		$	17.9		$	38		$	36.2
	Less income attributable to participating shares	(0.4		)	(0.7		)	(0.8		)	(1.3		)
	Less income attributable to noncontrolling interest	—			(0.1		)	(0.1		)	(0.2		)
	Net income attributable to AAR available to common shareholders	$	19.6		$	17.1		$	37.1		$	34.7
	Basic shares:
	Weighted average common shares outstanding	38.6			38.2			38.6			38.4
	Earnings per share — basic	$	0.51		$	0.45		$	0.96		$	0.9
	Diluted EPS:
	Net income attributable to AAR and noncontrolling interest	$	20		$	17.9		$	38		$	36.2
	Less income attributable to participating shares	(0.4		)	(0.7		)	(0.8		)	(1.3		)
	Less income attributable to noncontrolling interest	—			(0.1		)	(0.1		)	(0.2		)
	Add after-tax interest on convertible debt	—			1.2			—			2.4
	Net income attributable to AAR available to common shareholders	$	19.6		$	18.3		$	37.1		$	37.1
	Diluted shares:
	Weighted average common shares outstanding	38.6			38.2			38.6			38.4
	Additional shares from the assumed exercise of stock options	0.6			0.1			0.5			—
	Additional shares from the assumed conversion of convertible debt	—			3.2			—			3.2
	Weighted average common shares outstanding — diluted	39.2			41.5			39.1			41.6
	Earnings per share — diluted	$	0.5		$	0.44		$	0.95		$	0.89
	At November 30, 2013 and 2012, respectively, stock options to purchase 48,000 shares and 1,434,020 shares of common stock were outstanding, but were not included in the computation of diluted earnings per share because the exercise price of each of these options was greater than the average market price of the common shares during the interim periods then ended.

Program_Development_Costs

Program Development Costs	6 Months Ended
	Nov. 30, 2013
Program Development Costs	'
Program Development Costs	'
	Note 9 — Program Development Costs
	Our Cargo Systems unit was selected in June 2005 to provide cargo loading systems for the Airbus A400M Military Transport Aircraft (“A400M”).  During fiscal 2013, we delivered initial production units to Airbus, and the first revenue-producing unit was delivered in the first quarter of fiscal 2014.  We expect our portion of the revenue from this program to be approximately $250 million through fiscal 2020, based on current sales projections of the A400M and the agreed-upon fixed pricing for the items that we are now responsible for under the amended contract.
	As of November 30, 2013 and May 31, 2013, we have capitalized, net of reimbursements, $129.5 million and $130.9 million, respectively, of costs associated with the engineering and development of the cargo system.  Capitalized costs are broken out between current and non-current assets on the Condensed Consolidated Balance Sheets.  Current assets include $18.3 million and $6.0 million in Deposits, prepaids and other at November 30, 2013 and May 31, 2013, respectively and non-current assets include $111.2 million and $124.9 million in Capitalized program development costs at November 30, 2013 and May 31, 2013, respectively.  Sales and related cost of sales will be recognized on the units of delivery method.  In determining the recoverability of the capitalized program development costs, we have made certain judgments and estimates concerning expected revenues and the cost to manufacture the A400M cargo system.  Differences between actual results and our assumptions may result in our not fully recovering our program development costs, which could adversely affect our operating results and financial condition.

Business_Segment_Information

Business Segment Information	6 Months Ended
	Nov. 30, 2013
Business Segment Information	'
Business Segment Information	'
	Note 10 — Business Segment Information
	We report our activities in two business segments: Aviation Services and Technology Products.  Sales in the Aviation Services segment are derived from the sale and lease of a wide variety of new, overhauled, and repaired engine and airframe parts and components to the commercial aviation and government and defense markets.  We provide customized inventory supply chain management and performance-based logistics programs, aircraft component repair management services, and aircraft modifications.  The segment also includes repair, maintenance, and overhaul of aircraft and landing gear and expeditionary airlift services.  Cost of sales consists principally of the cost of product, direct labor, overhead, and aircraft maintenance costs.
	Sales in the Technology Products segment are derived from the engineering, designing, and manufacturing of containers, pallets, and shelters used to support the U.S. military’s requirements for a mobile and agile force and system integration services for specialized command and control systems.  The segment also manufactures heavy-duty pallets and lightweight cargo containers for the commercial market, in-plane cargo loading and handling systems for commercial and military applications, and steel and composite machined and fabricated parts, components and sub-systems for various aerospace and defense programs.  Cost of sales consists principally of the cost of material to manufacture products, direct labor and overhead.
	The accounting policies for the segments are the same as those described in Note 1 of Notes to Consolidated Financial Statements included in our annual report on Form 10-K for the year ended May 31, 2013.  Our chief operating decision making officer (Chief Executive Officer) evaluates performance based on the reportable segments and utilizes gross profit as a primary profitability measure.  The assets and certain expenses related to corporate activities are not allocated to the segments.  Our reportable segments are aligned principally around differences in products and services.
	Gross profit is calculated by subtracting cost of sales from sales.  Selected financial information for each segment is as follows:
		Three Months Ended						Six Months Ended
		November 30,						November 30,
		2013			2012			2013			2012
	Sales:
	Aviation Services	$	424.7		$	390.8		$	818.4		$	789
	Technology Products	116			122			236.8			274.3
		$	540.7		$	512.8		$	1,055.20		$	1,063.30
		Three Months Ended						Six Months Ended
		November 30,						November 30,
		2013			2012			2013			2012
	Gross profit:
	Aviation Services	$	71.3		$	67.4		$	136.8		$	128.8
	Technology Products	19.7			20			38.9			48.9
		$	91		$	87.4		$	175.7		$	177.7
	The following table reconciles segment gross profit to consolidated income before provision for income taxes.
		Three Months Ended						Six Months Ended
		November 30,						November 30,
		2013			2012			2013			2012
	Segment gross profit	$	91		$	87.4		$	175.7		$	177.7
	Selling, general and administrative	(51.1		)	(50.8		)	(98.8		)	(104.1		)
	Earnings from joint ventures	0.8			1.2			2			2.6
	Loss on extinguishment of debt	—			(0.1		)	—			(0.3		)
	Interest expense	(10.5		)	(10.8		)	(21.5		)	(21.4		)
	Interest income	0.3			0.3			0.6			0.7
	Income before provision for income taxes	$	30.5		$	27.2		$	58		$	55.2

Accounting_for_StockBased_Comp1

Accounting for Stock-Based Compensation (Tables)	6 Months Ended
	Nov. 30, 2013
Accounting for Stock-Based Compensation	'
Assumptions used in the Black-Scholes option pricing model to estimate the fair value of each stock option grant	'
		Six Months Ended
		November 30, 2013
	Risk-free interest rate	1.4	%
	Expected volatility of common stock	49.1	%
	Dividend yield	1.2	%
	Expected option term in years	5.2

Inventory_Tables

Inventory (Tables)	6 Months Ended
	Nov. 30, 2013
Inventory	'
Summary of inventories	'
		November 30,		May 31,
		2013		2013
	Raw materials and parts	$	103.5	$	83.9
	Work-in-process	74.6		84
	Purchased aircraft, parts, engines and components held for sale	285.7		285.8
		$	463.8	$	453.7

Supplemental_Cash_Flow_Informa1

Supplemental Cash Flow Information (Tables)	6 Months Ended
	Nov. 30, 2013
Supplemental Cash Flow Information	'
Schedule of supplemental information on cash flow	'
		Six Months Ended
		November 30,
		2013		2012
	Interest paid	$	17	$	14.5
	Income taxes paid	5.6		12.9
	Income tax refunds received	6.5		5.6

Financing_Arrangements_Tables

Financing Arrangements (Tables)	6 Months Ended
	Nov. 30, 2013
Financing Arrangements	'
Summary of carrying amount of debt	'
		November 30,			May 31,
		2013			2013
	Revolving credit facility expiring April 24, 2018 with interest payable monthly	$	100		$	120
	Secured credit facility (secured by aircraft and related engines and components) due April 23, 2015 with floating interest rate, payable monthly	34.6			39.2
	Note payable due March 9, 2017 with floating interest rate, payable semi-annually on June 1 and December 1	35			40
	Notes payable due January 15, 2022 with interest at 7.25% payable semi-annually on January 15 and July 15	333			333.4
	Convertible notes payable due March 1, 2014 with interest at 1.625% payable semi-annually on March 1 and September 1	67.6			65.9
	Convertible notes payable due March 1, 2016 with interest at 2.25% payable semi-annually on March 1 and September 1	44.6			43.5
	Other(1)	66			66.6
	Total debt	680.8			708.6
	Current maturities of debt	(87.3		)	(86.4		)
	Long-term debt	$	593.5		$	622.2
	(1)         Included in Other at November 30, 2013 and May 31, 2013, respectively, is (i) a note payable due March 15, 2014 of $0.5 million and $1.2 million, (ii) a mortgage loan (secured by Wood Dale, Illinois facility) due August 1, 2015 of $11.0 million and $11.0 million, (iii) convertible notes due February 1, 2015 of $29.5 million and $29.4 million, and (iv) an industrial revenue bond (secured by property, plant, and equipment) due August 1, 2018 of $25.0 million and $25.0 million.
Schedule of long-term debt and equity component (recorded in capital surplus, net of income tax benefit) of convertible notes	'
		November 30,			May 31,
		2013			2013
	Long-term debt:
	Principal amount	$	148.3		$	148.3
	Unamortized discount	(6.6		)	(9.5		)
	Net carrying amount	$	141.7		$	138.8
	Equity component, net of tax	$	75.3		$	75.3
Schedule of interest expense associated with the convertible notes	'
		Three Months Ended						Six Months Ended
		November 30,						November 30,
		2013			2012			2013		2012
	Coupon interest	$	0.9		$	1		$	1.7	$	2
	Amortization of deferred financing fees	0.1			0.1			0.2		0.3
	Amortization of discount	1.5			2.8			2.9		5.6
	Interest expense related to convertible notes	$	2.5		$	3.9		$	4.8	$	7.9

Derivative_Instruments_and_Hed1

Derivative Instruments and Hedging Activities (Tables)	6 Months Ended
	Nov. 30, 2013
Derivative Instruments and Hedging Activities	'
Schedule of fair value carrying amount of our interest rate derivatives	'
	Derivatives designated		November 30,			May 31,
	as hedging instruments	Balance Sheet Classification	2013			2013
	Interest rate cap	Long-term assets	$	0.1		$	0.1
	Interest rate swap	Long-term liabilities	(3.1		)	(3.6		)

Earnings_per_Share_Tables

Earnings per Share (Tables)	6 Months Ended
	Nov. 30, 2013
Earnings per Share	'
Reconciliation of the computations of basic and diluted earnings per share information	'
		Three Months Ended						Six Months Ended
		November 30,						November 30,
		2013			2012			2013			2012
	Basic EPS:
	Net income attributable to AAR and noncontrolling interest	$	20		$	17.9		$	38		$	36.2
	Less income attributable to participating shares	(0.4		)	(0.7		)	(0.8		)	(1.3		)
	Less income attributable to noncontrolling interest	—			(0.1		)	(0.1		)	(0.2		)
	Net income attributable to AAR available to common shareholders	$	19.6		$	17.1		$	37.1		$	34.7
	Basic shares:
	Weighted average common shares outstanding	38.6			38.2			38.6			38.4
	Earnings per share — basic	$	0.51		$	0.45		$	0.96		$	0.9
	Diluted EPS:
	Net income attributable to AAR and noncontrolling interest	$	20		$	17.9		$	38		$	36.2
	Less income attributable to participating shares	(0.4		)	(0.7		)	(0.8		)	(1.3		)
	Less income attributable to noncontrolling interest	—			(0.1		)	(0.1		)	(0.2		)
	Add after-tax interest on convertible debt	—			1.2			—			2.4
	Net income attributable to AAR available to common shareholders	$	19.6		$	18.3		$	37.1		$	37.1
	Diluted shares:
	Weighted average common shares outstanding	38.6			38.2			38.6			38.4
	Additional shares from the assumed exercise of stock options	0.6			0.1			0.5			—
	Additional shares from the assumed conversion of convertible debt	—			3.2			—			3.2
	Weighted average common shares outstanding — diluted	39.2			41.5			39.1			41.6
	Earnings per share — diluted	$	0.5		$	0.44		$	0.95		$	0.89

Business_Segment_Information_T

Business Segment Information (Tables)	6 Months Ended
	Nov. 30, 2013
Business Segment Information	'
Selected financial information for each reportable segment	'
		Three Months Ended						Six Months Ended
		November 30,						November 30,
		2013			2012			2013			2012
	Sales:
	Aviation Services	$	424.7		$	390.8		$	818.4		$	789
	Technology Products	116			122			236.8			274.3
		$	540.7		$	512.8		$	1,055.20		$	1,063.30
		Three Months Ended						Six Months Ended
		November 30,						November 30,
		2013			2012			2013			2012
	Gross profit:
	Aviation Services	$	71.3		$	67.4		$	136.8		$	128.8
	Technology Products	19.7			20			38.9			48.9
		$	91		$	87.4		$	175.7		$	177.7
Schedule of reconciliation of segment gross profit to consolidated income before provision for income taxes	'
		Three Months Ended						Six Months Ended
		November 30,						November 30,
		2013			2012			2013			2012
	Segment gross profit	$	91		$	87.4		$	175.7		$	177.7
	Selling, general and administrative	(51.1		)	(50.8		)	(98.8		)	(104.1		)
	Earnings from joint ventures	0.8			1.2			2			2.6
	Loss on extinguishment of debt	—			(0.1		)	—			(0.3		)
	Interest expense	(10.5		)	(10.8		)	(21.5		)	(21.4		)
	Interest income	0.3			0.3			0.6			0.7
	Income before provision for income taxes	$	30.5		$	27.2		$	58		$	55.2

Revenue_Recognition_Details

Revenue Recognition (Details) (USD $)	Nov. 30, 2013	31-May-13
In Millions, unless otherwise specified
Summary of Significant Accounting Policies	'	'
Unbilled accounts receivable related to KC10 supply agreement	$22.40	$28.40
Cost in excess of amount billed	$11.90	$9.90

Accounting_for_StockBased_Comp2

Accounting for Stock-Based Compensation (Details) (USD $)	3 Months Ended		6 Months Ended		3 Months Ended		6 Months Ended				1 Months Ended
In Millions, except Share data, unless otherwise specified	Nov. 30, 2013	Nov. 30, 2012	Nov. 30, 2013	Nov. 30, 2012	Nov. 30, 2013	Nov. 30, 2012	Nov. 30, 2013	Nov. 30, 2012	Nov. 30, 2013	Nov. 30, 2013	Jun. 30, 2013
	Stock options	Stock options	Stock options	Stock options	Restricted stock	Restricted stock	Restricted stock	Restricted stock	Performance-based restricted stock	Time-based restricted stock	Time-based restricted stock
											Board of Directors
Share-Based Compensation	'	'	'	'	'	'	'	'	'	'	'
Granted (in shares)	'	'	1,027,515	'	'	'	'	'	'	'	'
Granted (in dollars per share)	'	'	$25.43	'	'	'	'	'	'	'	'
Weighted average fair value of stock options granted (in dollars per share)	'	'	$10.24	'	'	'	'	'	'	'	'
Assumptions used in the Black-Scholes option pricing models to estimate the fair value of each stock option grant	'	'	'	'	'	'	'	'	'	'	'
Risk-free interest rate (as a percent)	'	'	1.40%	'	'	'	'	'	'	'	'
Expected volatility of common stock (as a percent)	'	'	49.10%	'	'	'	'	'	'	'	'
Dividend yield (as a percent)	'	'	1.20%	'	'	'	'	'	'	'	'
Expected option term	'	'	'5 years 2 months 12 days	'	'	'	'	'	'	'	'
Stock options, additional disclosures	'	'	'	'	'	'	'	'	'	'	'
Total intrinsic value of stock options exercised	'	'	$3.70	$0.10	'	'	'	'	'	'	'
Compensation expense	$1	$0.90	$1.50	$1.60	$1.40	$0.90	$2.50	$3.10	'	'	'
Granted (in shares)	'	'	'	'	'	'	'	'	60,808	60,808	45,000
Granted (in dollars per share)	'	'	'	'	'	'	'	'	$25.43	$25.43	$20.68

Inventory_Details

Inventory (Details) (USD $)	Nov. 30, 2013	31-May-13
In Millions, unless otherwise specified
Inventory	'	'
Raw materials and parts	$103.50	$83.90
Work-in-process	74.6	84
Purchased aircraft, parts, engines and components held for sale	285.7	285.8
Total inventories	$463.80	$453.70

Supplemental_Cash_Flow_Informa2

Supplemental Cash Flow Information (Details) (USD $)	6 Months Ended
In Millions, unless otherwise specified	Nov. 30, 2013	Nov. 30, 2012
Supplemental Cash Flow Information	'	'
Interest paid	$17	$14.50
Income taxes paid	5.6	12.9
Income tax refunds received	$6.50	$5.60

Financing_Arrangements_Details

Financing Arrangements (Details) (USD $)	3 Months Ended		6 Months Ended
In Millions, unless otherwise specified	Nov. 30, 2013	Nov. 30, 2012	Nov. 30, 2013	Nov. 30, 2012	31-May-13
Financing Arrangements	'	'	'	'	'
Total debt	$680.80	'	$680.80	'	$708.60
Current maturities of debt	-87.3	'	-87.3	'	-86.4
Long-term debt	593.5	'	593.5	'	622.2
Loss on extinguishment of debt	'	0.1	'	0.3	'
Face value of long-term debt	679.3	'	679.3	'	'
Estimated fair value of long-term debt	705.8	'	705.8	'	'
Long-term debt:	'	'	'	'	'
Principal amount	679.3	'	679.3	'	'
Interest expense	'	'	'	'	'
Amortization of discount	'	'	3	5.7	'
Revolving credit facility expiring April 24, 2018 with interest payable monthly	'	'	'	'	'
Financing Arrangements	'	'	'	'	'
Total debt	100	'	100	'	120
Secured credit facility (secured by aircraft and related engines and components) due April 23, 2015 with floating interest rate, payable monthly	'	'	'	'	'
Financing Arrangements	'	'	'	'	'
Total debt	34.6	'	34.6	'	39.2
Note payable due March 9, 2017 with floating interest rate, payable semi-annually on June 1 and December 1	'	'	'	'	'
Financing Arrangements	'	'	'	'	'
Total debt	35	'	35	'	40
Notes payable due January 15, 2022 with interest at 7.25% payable semi-annually on January 15 and July 15	'	'	'	'	'
Financing Arrangements	'	'	'	'	'
Interest rate (as a percent)	7.25%	'	7.25%	'	'
Total debt	333	'	333	'	333.4
Convertible notes payable	'	'	'	'	'
Financing Arrangements	'	'	'	'	'
Face value of long-term debt	148.3	'	148.3	'	148.3
Long-term debt:	'	'	'	'	'
Principal amount	148.3	'	148.3	'	148.3
Unamortized discount	-6.6	'	-6.6	'	-9.5
Net carrying amount	141.7	'	141.7	'	138.8
Equity component, net of tax	75.3	'	75.3	'	75.3
Interest expense	'	'	'	'	'
Coupon interest	0.9	1	1.7	2	'
Amortization of deferred financing fees	0.1	0.1	0.2	0.3	'
Amortization of discount	1.5	2.8	2.9	5.6	'
Interest expense related to convertible notes	2.5	3.9	4.8	7.9	'
Convertible notes payable due March 1, 2014 with interest at 1.625% payable semi-annually on March 1 and September 1	'	'	'	'	'
Financing Arrangements	'	'	'	'	'
Interest rate (as a percent)	1.63%	1.63%	1.63%	1.63%	'
Total debt	67.6	'	67.6	'	65.9
Amount of convertible notes repurchased	'	6.4	'	6.4	'
Cash paid for convertible notes repurchased	'	6.1	'	6.1	'
Long-term debt:	'	'	'	'	'
Effective interest rate (as a Percent)	6.82%	'	6.82%	'	'
Convertible notes payable due February 1, 2015 with interest at 1.75% payable semi-annually on February 1 and August 1	'	'	'	'	'
Long-term debt:	'	'	'	'	'
Net carrying amount	29.5	'	29.5	'	29.4
Convertible notes payable due March 1, 2016 with interest at 2.25% payable semi-annually on March 1 and September 1	'	'	'	'	'
Financing Arrangements	'	'	'	'	'
Interest rate (as a percent)	2.25%	2.25%	2.25%	2.25%	'
Total debt	44.6	'	44.6	'	43.5
Amount of convertible notes repurchased	'	5.5	'	5.5	'
Cash paid for convertible notes repurchased	'	4.9	'	4.9	'
Long-term debt:	'	'	'	'	'
Effective interest rate (as a Percent)	7.41%	'	7.41%	'	'
Convertible notes payable due February 1, 2026 with interest at 1.75% payable semi-annually on February 1 and August 1	'	'	'	'	'
Financing Arrangements	'	'	'	'	'
Interest rate (as a percent)	'	1.75%	'	1.75%	'
Amount of convertible notes repurchased	'	11	'	11	'
Cash paid for convertible notes repurchased	'	11	'	11	'
Long-term debt:	'	'	'	'	'
Effective interest rate (as a Percent)	5.00%	'	5.00%	'	'
Note payable due March 15, 2014	'	'	'	'	'
Long-term debt:	'	'	'	'	'
Net carrying amount	0.5	'	0.5	'	1.2
Mortgage loan (secured by Wood Dale, Illinois facility) due August 1, 2015 with interest at 5.01%	'	'	'	'	'
Long-term debt:	'	'	'	'	'
Net carrying amount	11	'	11	'	11
Industrial revenue bond (secured by property, plant and equipment) due August 1, 2018	'	'	'	'	'
Long-term debt:	'	'	'	'	'
Net carrying amount	25	'	25	'	25
Other	'	'	'	'	'
Financing Arrangements	'	'	'	'	'
Total debt	$66	'	$66	'	$66.60

Derivative_Instruments_and_Hed2

Derivative Instruments and Hedging Activities (Details) (USD $)	Nov. 30, 2013	31-May-13
In Millions, unless otherwise specified
Derivative Instruments and Hedging Activities	'	'
Number of derivative financial instruments	2	'
Interest rate cap | Derivatives designated as hedging instruments:	'	'
Fair value carrying amount of the Company's interest rate derivatives	'	'
Derivative Assets	$0.10	$0.10
Interest rate cap | Derivatives designated as hedging instruments: | Cash flow hedges	'	'
Derivative Instruments and Hedging Activities	'	'
Notional amount under revolving credit agreement	50	'
Interest rate swap | Derivatives designated as hedging instruments:	'	'
Fair value carrying amount of the Company's interest rate derivatives	'	'
Derivative Liabilities	-3.1	-3.6
Interest rate swap | Derivatives designated as hedging instruments: | Cash flow hedges	'	'
Derivative Instruments and Hedging Activities	'	'
Notional amount under revolving credit agreement	$50	'

Derivative_Instruments_and_Hed3

Derivative Instruments and Hedging Activities (Details 2) (Cash flow hedges, USD $)	3 Months Ended		6 Months Ended
In Millions, unless otherwise specified	Nov. 30, 2013	Nov. 30, 2012	Nov. 30, 2013	Nov. 30, 2012
Cash flow hedges	'	'	'	'
Impact of the interest rate swap and interest cap agreement on the condensed consolidated statement of income	'	'	'	'
Amount of unrealized (loss) gain recorded in other accumulated comprehensive income (loss)	($0.60)	$0	$0.30	$0.40

Earnings_per_Share_Details

Earnings per Share (Details) (USD $)	3 Months Ended		6 Months Ended
In Millions, except Share data, unless otherwise specified	Nov. 30, 2013	Nov. 30, 2012	Nov. 30, 2013	Nov. 30, 2012
Earnings per Share	'	'	'	'
Effect to the participating securities as result of net loss	'	'	$0	'
Basic EPS:	'	'	'	'
Net income attributable to AAR and noncontrolling interest	20	17.9	38	36.2
Less income attributable to participating shares	-0.4	-0.7	-0.8	-1.3
Less income attributable to noncontrolling interest	'	-0.1	-0.1	-0.2
Net income attributable to AAR available to common shareholders	19.6	17.1	37.1	34.7
Basic shares:	'	'	'	'
Weighted average common shares outstanding	38,600,000	38,200,000	38,600,000	38,400,000
Earnings per share - basic:	'	'	'	'
Earnings per share - basic (in dollars per share)	$0.51	$0.45	$0.96	$0.90
Diluted EPS:	'	'	'	'
Net income attributable to AAR and noncontrolling interest	20	17.9	38	36.2
Less income attributable to participating shares	-0.4	-0.7	-0.8	-1.3
Less income attributable to noncontrolling interest	'	-0.1	-0.1	-0.2
Add after-tax interest on convertible debt	'	1.2	'	2.4
Net income attributable to AAR available to common shareholders	$19.60	$18.30	$37.10	$37.10
Diluted shares:	'	'	'	'
Weighted average common shares outstanding	38,600,000	38,200,000	38,600,000	38,400,000
Additional shares from the assumed exercise of stock options	600,000	100,000	500,000	'
Additional shares from the assumed conversion of convertible debt	'	3,200,000	'	3,200,000
Weighted average common shares outstanding - diluted	39,200,000	41,500,000	39,100,000	41,600,000
Earnings per share - diluted:	'	'	'	'
Earnings per share - diluted (in dollars per share)	$0.50	$0.44	$0.95	$0.89
Antidilutive stock options excluded from the computation of diluted earnings per share (in shares)	'	'	48,000	1,434,020

Program_Development_Costs_Deta

Program Development Costs (Details) (USD $)	Nov. 30, 2013	31-May-13
In Millions, unless otherwise specified
Program Development Costs	'	'
Expected revenue from cargo loading system program	$250	'
Net costs capitalized associated with the engineering and development of the cargo system	129.5	130.9
Net costs capitalized associated with the engineering and development of the cargo system, current	18.3	6
Net costs capitalized associated with the engineering and development of the cargo system, non-current	$111.20	$124.90

Business_Segment_Information_D

Business Segment Information (Details) (USD $)	3 Months Ended		6 Months Ended
In Millions, unless otherwise specified	Nov. 30, 2013	Nov. 30, 2012	Nov. 30, 2013	Nov. 30, 2012
			item
Business Segment Information	'	'	'	'
Number of business segments	'	'	2	'
Business Segment Information	'	'	'	'
Sales	$540.70	$512.80	$1,055.20	$1,063.30
Gross Profit	91	87.4	175.7	177.7
Aviation Services	'	'	'	'
Business Segment Information	'	'	'	'
Sales	424.7	390.8	818.4	789
Gross Profit	71.3	67.4	136.8	128.8
Technology Products	'	'	'	'
Business Segment Information	'	'	'	'
Sales	116	122	236.8	274.3
Gross Profit	$19.70	$20	$38.90	$48.90

Business_Segment_Information_D1

Business Segment Information (Details 2) (USD $)	3 Months Ended		6 Months Ended
In Millions, unless otherwise specified	Nov. 30, 2013	Nov. 30, 2012	Nov. 30, 2013	Nov. 30, 2012
Reconciliation of segment gross profit to consolidated income before provision for income taxes	'	'	'	'
Segment gross profit	$91	$87.40	$175.70	$177.70
Selling, general and administrative	-51.1	-50.8	-98.8	-104.1
Earnings from joint ventures	0.8	1.2	2	2.6
Loss on extinguishment of debt	'	-0.1	'	-0.3
Interest expense	-10.5	-10.8	-21.5	-21.4
Interest income	0.3	0.3	0.6	0.7
Income before provision for income taxes	$30.50	$27.20	$58	$55.20