Goodwill and Intangible Assets, Net - Schedule of Goodwill (Details) - USD ($) $ in Thousands		9 Months Ended
Oct. 21, 2019	Sep. 30, 2020
Goodwill [Roll Forward]
Beginning balance		$ 104,963
Goodwill acquired	$ 42,100	0
Measurement period adjustment		699
Ending balance		105,662
Alarm.com
Goodwill [Roll Forward]
Beginning balance		104,963
Goodwill acquired		0
Measurement period adjustment		699
Ending balance		105,662
Other
Goodwill [Roll Forward]
Beginning balance		0
Goodwill acquired		0
Measurement period adjustment		0
Ending balance		$ 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
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
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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
-Publisher FASB
-Name Accounting Standards Codification
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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