v3.7.0.1
Document and Entity Information - shares
shares in Millions
3 Months Ended
Mar. 31, 2017
Apr. 30, 2017
Document And Entity Information [Abstract]    
Document Type 10-Q  
Amendment Flag false  
Document Period End Date Mar. 31, 2017  
Document Fiscal Year Focus 2017  
Document Fiscal Period Focus Q1  
Trading Symbol AJRD  
Entity Registrant Name AEROJET ROCKETDYNE HOLDINGS, INC.  
Entity Central Index Key 0000040888  
Current Fiscal Year End Date --12-31  
Entity Filer Category Large Accelerated Filer  
Entity Common Stock, Shares Outstanding   74.5