Debt, Commitments and Contingencies - Legal Proceedings (Details) - Pending Litigation - patent							1 Months Ended
	Jan. 31, 2020	Oct. 22, 2019	Jul. 24, 2019	Jun. 26, 2017	Aug. 19, 2016	Jun. 02, 2015	Sep. 30, 2017	May 31, 2017	Mar. 31, 2017
Vivint, Inc. vs. Alarm.com Holdings, Inc
Loss Contingencies [Line Items]
Number of patents allegedly infringed upon by the company			2	4	5	6		3	2
Number of patents under reexamination							2
Number of patents allegedly infringed by elements in solution						1
EcoFactor, Inc. vs. Alarm.com Holdings, Inc.
Loss Contingencies [Line Items]
Number of patents allegedly infringed upon by the company	4	3