Goodwill and Intangible Assets, Net - Schedule of Goodwill (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Goodwill [Roll Forward]
Beginning balance	$ 104,963	$ 63,591
Goodwill acquired	7,176	41,372
Measurement period adjustment	699
Ending balance	112,838	104,963
Alarm.com
Goodwill [Roll Forward]
Beginning balance	104,963	63,591
Goodwill acquired	7,176	41,372
Measurement period adjustment	699
Ending balance	112,838	104,963
Other
Goodwill [Roll Forward]
Beginning balance	0	0
Goodwill acquired	0	0
Measurement period adjustment	0
Ending balance	$ 0	$ 0

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 210
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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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