Investments in Unconsolidated Entities - Narrative (Details) - USD ($) $ in Thousands				1 Months Ended					9 Months Ended
	Jun. 06, 2025	May 30, 2025	Apr. 28, 2025	Dec. 31, 2024	May 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Feb. 28, 2021	Sep. 30, 2025	Sep. 30, 2024	Jun. 11, 2025	Jul. 31, 2019
Schedule of Equity Method Investments [Line Items]
Cash purchase of shares									$ 175,057	$ 7,052
Hardware Supplier
Schedule of Equity Method Investments [Line Items]
Conversion of outstanding notes receivable												$ 5,600
Conversion of outstanding notes receivable (in shares)												9,520,832
Investment				$ 5,600					$ 5,600
Safe Haven and All Access
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage									32.50%
Safe Haven and All Access \| Minimum \| Trade Names and Customer Relationships
Schedule of Equity Method Investments [Line Items]
Finite-lived intangible asset, useful life									9 years
Safe Haven and All Access \| Maximum \| Trade Names and Customer Relationships
Schedule of Equity Method Investments [Line Items]
Finite-lived intangible asset, useful life									14 years
Safe Haven
Schedule of Equity Method Investments [Line Items]
Payments to acquire equity method investments		$ 119,300
Equity method investment, ownership percentage		32.50%
Payments to acquire equity method investments, holdback amount		$ 6,300
All Access
Schedule of Equity Method Investments [Line Items]
Payments to acquire equity method investments	$ 19,200
Equity method investment, ownership percentage	32.50%
Payments to acquire equity method investments, holdback amount	$ 1,000
Safe Streets
Schedule of Equity Method Investments [Line Items]
Payments to acquire equity method investments			$ 29,100
Equity method investment, ownership percentage			24.70%						24.70%
Safe Streets \| Trade Name
Schedule of Equity Method Investments [Line Items]
Finite-lived intangible asset, useful life									10 years
Safe Streets \| Customer Relationships
Schedule of Equity Method Investments [Line Items]
Finite-lived intangible asset, useful life									11 years
Technology Partner
Schedule of Equity Method Investments [Line Items]
Investment				5,700					$ 5,700
Cash purchase of shares								$ 5,000
Technology Partner \| Series B-2 Preferred Stock
Schedule of Equity Method Investments [Line Items]
Shares purchased (in shares)								1,000,000
Technology Partner, Two
Schedule of Equity Method Investments [Line Items]
Investment				5,100					5,100
Cash purchase of shares							$ 5,100
Technology Partner, Two \| Series A Preferred Stock
Schedule of Equity Method Investments [Line Items]
Shares purchased (in shares)							4,231,717
Technology Partner, Three
Schedule of Equity Method Investments [Line Items]
Investment				4,500					$ 4,500		$ 4,500
Cash purchase of shares				$ 1,500	$ 1,500	$ 1,500
Equity ownership percentage											25.90%

Alarm.com Holdings, Inc. 10-Q