Segment Information (Details) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2015 USD ($)	Jun. 30, 2014 USD ($)	Jun. 30, 2015 USD ($) segment	Jun. 30, 2014 USD ($)	Dec. 31, 2014 USD ($)
Segment Reporting [Abstract]
Number of reportable segments \| segment			2
Segment Reporting Information [Line Items]
Revenue	$ 51,949	$ 42,078	$ 97,960	$ 78,929
Operating income / (loss)	4,277	3,562	9,403	10,680
Total Assets	119,222		119,222		$ 120,932
Operating Segments \| Alarm.com
Segment Reporting Information [Line Items]
Revenue	50,753	42,147	95,618	78,674
Operating income / (loss)	9,370	7,033	18,330	17,090
Total Assets	104,579		104,579		108,935
Operating Segments \| Other
Segment Reporting Information [Line Items]
Revenue	1,580	129	3,641	587
Operating income / (loss)	(5,082)	(3,341)	(8,906)	(6,279)
Total Assets	14,643		14,643		$ 11,997
Intersegment Eliminations \| Alarm.com
Segment Reporting Information [Line Items]
Revenue	(130)	(198)	(520)	(332)
Operating income / (loss)	(33)	(57)	(171)	(80)
Intersegment Eliminations \| Other
Segment Reporting Information [Line Items]
Revenue	(254)	0	(779)	0
Operating income / (loss)	$ 22	$ (73)	$ 150	$ (51)
Segment Concentration Risk \| Revenue \| Alarm.com
Segment Reporting Information [Line Items]
Concentration risk percentage (more than)	97.00%	97.00%	97.00%	97.00%

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.

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