Segment Information (Details) $ in Thousands	3 Months Ended
Mar. 31, 2017 USD ($) segment	Mar. 31, 2016 USD ($)	Dec. 31, 2016 USD ($)
Segment Reporting [Abstract]
Number of reportable segments \| segment	2
Segment Reporting Information [Line Items]
Revenue	$ 74,194	$ 59,043
Operating income	4,485	4,261
Total Assets	335,640		$ 261,245
Operating Segments \| Alarm.com
Segment Reporting Information [Line Items]
Revenue	70,512	56,010
Operating income	6,584	6,867
Total Assets	316,924		246,798
Operating Segments \| Other
Segment Reporting Information [Line Items]
Revenue	4,452	3,847
Operating income	(2,213)	(2,683)
Total Assets	18,716		14,447
Intersegment Eliminations \| Alarm.com
Segment Reporting Information [Line Items]
Revenue	(649)	(586)
Operating income	(22)	(47)
Total Assets	0		0
Intersegment Eliminations \| Other
Segment Reporting Information [Line Items]
Revenue	(121)	(228)
Operating income	136	$ 124
Total Assets	$ 0		$ 0
Segment Concentration Risk \| Revenue \| Alarm.com
Segment Reporting Information [Line Items]
Concentration risk percentage	94.00%	94.00%

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(12))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-Section 50
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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