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Gain Contingency, Number of Patents in Suit Appealed

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Loss Contingency, Damages Sought, Value, Punitive

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Loss Contingency, Patents Allegedly Infringed, Number of Elements In Solution Potentially Infringed

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Loss Contingency, Patents Allegedly Infringed, Number of Patents Allegedly Infringed by Elements in Solution

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Loss Contingency, Patents Under Reexamination, Number

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Number Of Service Providers

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Operating Lease, Additional Leasehold Improvement Allowance

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Operating Lease, Available Leasehold Improvement Allowance

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Area of a real estate property.

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Carrying amount as of the balance sheet date of obligations due all related parties. For classified balance sheets, represents the current portion of such liabilities (due within one year or within the normal operating cycle if longer).

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Portion of the carrying amount as of the balance sheet date of obligations due all related parties that is payable after one year or beyond the normal operating cycle if longer.

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Number of entity's patents that another entity has allegedly infringed.

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Amount of rent expense incurred for leased assets, including but not limited to, furniture and equipment, that is not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

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Term of lessee's operating lease renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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Number of another entity's patents that the entity has allegedly infringed.

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Debt, Commitments and Contingencies - Commitments and Contingencies (Details)							1 Months Ended			12 Months Ended
	Aug. 24, 2017 claim	Jun. 26, 2017 patent	Apr. 25, 2017 claim	Aug. 19, 2016 patent	Feb. 09, 2016 USD ($) service_provider	Jun. 02, 2015 patent element	Mar. 31, 2017 patent	Sep. 30, 2015 patent	Aug. 31, 2014 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($) ft²	Dec. 31, 2015 USD ($)
Related Party Transaction [Line Items]
Renewal term option (years)									5 years
Available leasehold improvement allowance									$ 8,000,000	$ 9,700,000
Additional office space (square feet) \| ft²											30,662
Increase in tenant improvement allowance											$ 1,700,000
Rent expense										6,200,000	4,800,000	$ 4,900,000
Pending Litigation
Related Party Transaction [Line Items]
Compensatory damages sought					$ 7,000,000
Punitive damages sought					$ 350,000
Number of service providers \| service_provider					1
Number of patents instituted \| patent								1
Number of patents appealed \| patent								1
Alarm.com and ICN Acquisition, LLC vs. Protect America,Inc. and SecureNet Technologies, LLC \| Pending Litigation
Related Party Transaction [Line Items]
Number of patents allegedly infringed upon \| claim			1
Alarm.com and ICN Acquisition, LLC vs. ipDatatel \| Pending Litigation
Related Party Transaction [Line Items]
Number of patents allegedly infringed upon \| claim	1
Vivint, Inc. vs. Alarm.com Holdings, Inc \| Pending Litigation
Related Party Transaction [Line Items]
Number of patents allegedly infringed \| patent		4		5		6	2
Number of patents under reexamination \| patent		2
Number of elements of a solution in a patent, potentially infringed (or more) \| element						1
Number of patents allegedly infringed by elements in solution \| patent						1
Line of Credit \| 2014 Facility \| Letter of Credit
Related Party Transaction [Line Items]
Letters of credit outstanding										0	0
Founder and President \| Repurchase of Subsidiary Units, February 2011
Related Party Transaction [Line Items]
Due to related parties, current										2,800,000	2,500,000
Due to related parties, noncurrent										$ 400,000	$ 300,000