Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2017	May 01, 2017
Document and Entity Information [Abstract]
Entity Registrant Name	ALARM.COM HOLDINGS, INC.
Entity Central Index Key	0001459200
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Document Type	10-Q
Document Period End Date	Mar. 31, 2017
Document Fiscal Year Focus	2017
Document Fiscal Period Focus	Q1
Amendment Flag	false
Entity Common Stock, Shares Outstanding		46,318,997