Document and Entity Information
6 Months Ended
Nov. 30, 2018
Document and Entity Information  
Entity Registrant Name AAR CORP
Entity Central Index Key 0000001750
Document Type 10-Q
Document Period End Date Nov. 30, 2018
Amendment Flag false
Current Fiscal Year End Date --05-31
Entity Current Reporting Status Yes
Entity Small Business false
Entity Emerging Growth Company false
Entity Filer Category Large Accelerated Filer
Entity Common Stock, Shares Outstanding 35,095,139
Document Fiscal Year Focus 2019
Document Fiscal Period Focus Q2