Summary of Significant Accounting Policies - Goodwill (Details)	12 Months Ended
Dec. 31, 2016
Accounting Policies [Abstract]
Quantitative analysis period (in years)	3 years
Alarm.com
Goodwill [Line Items]
Reporting unit, percentage of fair value that exceeded carrying value (more than)	100.00%

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration