Segment Information - Narrative (Details)	3 Months Ended	9 Months Ended
Sep. 30, 2025 USD ($)	Sep. 30, 2024 USD ($)	Sep. 30, 2025 USD ($) segment	Sep. 30, 2024 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments \| segment			2
Total revenue	$ 256,400,000	$ 240,497,000	$ 749,530,000	$ 697,587,000
Alarm.com \| Operating Segments
Segment Reporting Information [Line Items]
Total revenue	231,587,000	221,916,000	687,156,000	650,456,000
Additions to property and equipment	3,900,000	12,600,000	16,900,000	18,400,000
Alarm.com \| Software License Revenue
Segment Reporting Information [Line Items]
Total revenue	4,300,000	5,000,000.0	13,500,000	15,400,000
Other \| Operating Segments
Segment Reporting Information [Line Items]
Total revenue	25,854,000	19,567,000	65,532,000	49,987,000
Additions to property and equipment	100,000	100,000	100,000	100,000
Other \| Software License Revenue
Segment Reporting Information [Line Items]
Total revenue	$ 0	$ 0	$ 0	$ 0
Revenue \| Segment Concentration Risk \| Alarm.com
Segment Reporting Information [Line Items]
Concentration risk percentage	90.00%	92.00%	91.00%	93.00%

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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