Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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The current period expense charged against earnings on long-lived, physical assets not used in production, and which are not intended for resale, to allocate or recognize the cost of such assets over their useful lives; or to record the reduction in book value of an intangible asset over the benefit period of such asset; or to reflect consumption during the period of an asset that is not used in production.

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Revenue from multiple-deliverable arrangements that include licensing fees and services revenue. Licensing revenue is consideration received from another party for the right to use, but not own, certain of the entity's intangible assets. Licensing arrangements include, but are not limited to, rights to use a patent, copyright, technology, manufacturing process, software or trademark. Licensing fees are generally, but not always, fixed as to amount and not dependent upon the revenue generated by the licensing party. An entity may receive licensing fees for licenses that also generate royalty payments to the entity. Services revenue may be derived by providing other, nonspecified, services during the reporting period.

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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The net result for the period of deducting operating expenses from operating revenues.

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The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets.

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Aggregate revenue during the period from the sale of goods in the normal course of business, after deducting returns, allowances and discounts.

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Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

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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.

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Segment Information (Details) $ in Thousands	3 Months Ended								12 Months Ended
Segment Information (Details) $ in Thousands	Dec. 31, 2017 USD ($)	Sep. 30, 2017 USD ($)	Jun. 30, 2017 USD ($)	Mar. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Sep. 30, 2016 USD ($)	Jun. 30, 2016 USD ($)	Mar. 31, 2016 USD ($)	Dec. 31, 2017 USD ($) segment	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Segment Reporting [Abstract]
Number of reportable segments \| segment									2
Segment Reporting Information [Line Items]
SaaS and license revenue									$ 236,283	$ 173,540	$ 140,936
Hardware and other revenue									102,654	87,566	67,952
Total revenue	$ 88,793	$ 89,962	$ 85,988	$ 74,194	$ 69,794	$ 67,846	$ 64,423	$ 59,043	338,937	261,106	208,888
Operating income / (loss)									33,374	14,058	17,991
Assets	371,641				261,245				371,641	261,245
Amortization and depreciation									17,734	6,490	5,808
Additions to property and equipment									10,464	9,055	10,347
Alarm.com
Segment Reporting Information [Line Items]
Amortization and depreciation									17,400	6,300	5,500
Additions to property and equipment									9,300	5,700	10,200
Other
Segment Reporting Information [Line Items]
Amortization and depreciation									300	200	300
Additions to property and equipment									100	100	200
Operating Segments \| Alarm.com
Segment Reporting Information [Line Items]
SaaS and license revenue									227,583	168,732	139,036
Hardware and other revenue									92,445	79,049	63,716
Total revenue									320,028	247,781	202,752
Operating income / (loss)									41,439	21,282	38,437
Assets	352,766				246,798				352,766	246,798
Operating Segments \| Other
Segment Reporting Information [Line Items]
SaaS and license revenue									8,700	4,808	1,928
Hardware and other revenue									15,154	14,018	7,124
Total revenue									23,854	18,826	9,052
Operating income / (loss)									(8,248)	(7,229)	(20,151)
Assets	18,875				14,447				18,875	14,447
Intersegment Eliminations \| Alarm.com
Segment Reporting Information [Line Items]
SaaS and license revenue									0	0	(28)
Hardware and other revenue									(2,945)	(2,863)	(924)
Total revenue									(2,945)	(2,863)	(952)
Operating income / (loss)									(175)	(312)	(279)
Assets	0				0				0	0
Intersegment Eliminations \| Other
Segment Reporting Information [Line Items]
SaaS and license revenue									0	0	0
Hardware and other revenue									(2,000)	(2,638)	(1,964)
Total revenue									(2,000)	(2,638)	(1,964)
Operating income / (loss)									358	317	$ (16)
Assets	$ 0				$ 0				$ 0	$ 0
Segment Concentration Risk \| Revenue \| Alarm.com
Segment Reporting Information [Line Items]
Concentration risk percentage (percent)									94.00%	94.00%	97.00%