Document and Entity Information
6 Months Ended
Sep. 30, 2014
Oct. 27, 2014
Common stock, Class A
Oct. 27, 2014
Non-voting common stock, Class B
Oct. 27, 2014
Restricted common stock, Class C
Oct. 27, 2014
Special voting common stock, Class E
Document and Entity Information [Abstract]          
Entity Registrant Name Booz Allen Hamilton Holding Corp        
Entity Central Index Key 0001443646        
Document Type 10-Q        
Document Period End Date Sep. 30, 2014        
Amendment Flag false        
Document Fiscal Year Focus 2015        
Document Fiscal Period Focus Q2        
Current Fiscal Year End Date --03-31        
Entity Filer Category Accelerated Filer        
Entity Listings [Line Items]          
Entity Common Stock, Shares Outstanding   148,805,550 0 0 1,865,618