Document and Entity Information	9 Months Ended
	Dec. 31, 2014	Jan. 23, 2015
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	Dec. 31, 2014
Amendment Flag	false
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	Q3
Current Fiscal Year End Date	--03-31
Entity Filer Category	Large Accelerated Filer
Common stock, Class A
Entity Listings [Line Items]
Entity Common Stock, Shares Outstanding		147,908,527
Non-voting common stock, Class B
Entity Listings [Line Items]
Entity Common Stock, Shares Outstanding		0
Restricted common stock, Class C
Entity Listings [Line Items]
Entity Common Stock, Shares Outstanding		0
Special voting common stock, Class E
Entity Listings [Line Items]
Entity Common Stock, Shares Outstanding		1,851,590