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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=99380562&loc=d3e13770-109266

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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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Goodwill and Intangible Assets, Net - Schedule of Goodwill (Details) - USD ($) $ in Thousands			12 Months Ended
	Mar. 08, 2017	Jan. 01, 2017	Dec. 31, 2018	Dec. 31, 2017
Goodwill [Roll Forward]
Beginning balance		$ 24,723	$ 63,591	$ 24,723
Goodwill acquired			0	38,868
Ending balance			63,591	63,591
Alarm.com
Goodwill [Roll Forward]
Beginning balance		24,723	63,591	24,723
Goodwill acquired			0	38,868
Ending balance			63,591	63,591
Other
Goodwill [Roll Forward]
Beginning balance		0	0	0
Goodwill acquired			0	0
Ending balance			$ 0	$ 0
ObjectVideo
Goodwill [Roll Forward]
Goodwill acquired		2,300
Ending balance		$ 2,258
Connect And Piper
Goodwill [Roll Forward]
Goodwill acquired	$ 36,600
Ending balance	$ 36,610