Revenue Revenue (Policies)	6 Months Ended
Jun. 30, 2021
Revenue [Abstract]
Receivable [Policy Text Block]	Accounts Receivable, netAccounts receivable represent unconditional rights to consideration due from customers in the ordinary course of business and are generally due in one year or less. Accounts receivable are recorded at amortized cost less an allowance for credit losses that are not expected to be recovered. The allowance for credit losses is recognized at inception and is reassessed each reporting period.
Revenue Outright Sale Policy [Policy Text Block]	In transactions involving systems sold outright to the customer (referred to as outright sales), the Company’s performance obligations generally include the sale and installation of the system as well as any monitoring and related services. For such arrangements, the Company allocates a portion of the transaction price to each performance obligation based on relative standalone selling price, which is determined using observable internal or external pricing and profitability metrics. The portion of the transaction price associated with the sale and installation of a system is recognized either at a point in time or over time based upon the nature of the transaction and contractual terms and is reflected in installation and other revenue in the Condensed Consolidated Statements of Operations. For revenue recognized over time, progress toward complete satisfaction of the performance obligation is primarily measured using a cost-to-cost measure of progress method. The cost input that drives revenue recognition for contracts where revenue is recognized over time is based primarily on contract cost incurred to date compared to total estimated contract cost. This measure of progress method includes forecasts based on the best information available and reflects the Company’s judgment to faithfully depict the value of the services transferred to the customer. The portion of the transaction price associated with monitoring and related services revenue is recognized when services are provided to the customer and is reflected in monitoring and related services revenue in the Condensed Consolidated Statements of Operations.Revenue from product sales related to systems sold under a customer-owned model was $178 million and $259 million for the three months ended June 30, 2021 and 2020, respectively, and $381 million and $553 million for the six months ended June 30, 2021 and 2020, respectively. Cost of revenue from product sales related to systems sold under a customer-owned model was $147 million and $191 million for the three months ended June 30, 2021 and 2020, respectively, and $307 million and $403 million for the six months ended June 30, 2021 and 2020, respectively.
Revenue from Contract with Customer [Policy Text Block]	The Company generates revenue primarily through contractual monthly recurring fees received for monitoring and related services provided to customers. In transactions in which the Company provides monitoring and related services but retains ownership of the security system, the Company’s performance obligations primarily include monitoring, related services (such as maintenance agreements), and a material right associated with the one-time non-refundable fees in connection with the initiation of a monitoring contract that the customer will not be required to pay again upon a renewal of the contract (referred to as deferred subscriber acquisition revenue). The portion of the transaction price associated with monitoring and related services revenue is recognized when the services are provided to the customer and is reflected in monitoring and related services revenue in the Condensed Consolidated Statements of Operations. Early termination of the contract by the customer results in a termination charge in accordance with the terms of the contract. Contract termination charges are recognized in revenue when collectability is probable and are reflected in monitoring and related services revenue in the Condensed Consolidated Statements of Operations. The Company records revenue in the Condensed Consolidated Statements of Operations net of sales and other taxes. Amounts collected from customers for sales and other taxes are reported as a liability net of the related amounts remitted. Customer billings for services not yet rendered are deferred and recognized as revenue as services are provided. These fees are recorded as current deferred revenue in the Condensed Consolidated Balance Sheets as the Company expects to satisfy any remaining performance obligations, as well as recognize the related revenue, within the next twelve months. Accordingly, the Company has applied the practical expedient regarding deferred revenue to exclude the value of remaining performance obligations if (i) the contract has an original expected term of one year or less or (ii) the Company recognizes revenue in proportion to the amount it has the right to invoice for services performed.
Deferred Subscriber Acquisition Costs [Policy Text Block]	Deferred subscriber acquisition costs represent selling expenses (primarily commissions) that are incremental to acquiring customers. Amortization expense relating to deferred subscriber acquisition costs, which is included in selling, general, and administrative expenses in the Condensed Consolidated Statements of Operations was $30 million and $23 million for the three months ended June 30, 2021 and 2020, respectively, and $59 million and $45 million for the six months ended June 30, 2021 and 2020, respectively.
Financing Receivable, Allowance for Credit Losses, Policy for Uncollectible Amounts [Policy Text Block]	Retail Installment Contract Receivables, net During February 2020, the Company introduced a new retail installment contract option that allows qualifying residential customers to pay the fees due at installation over a 24-, 36-, or 60-month interest-free period. The financing component of the Company’s retail installment contract receivables is not significant. Retail installment contracts are available for residential transactions occurring under both Company-owned and customer-owned models. When originating a retail installment contract, the Company utilizes external credit scores to assess credit quality of a customer and to determine eligibility for the retail installment contract. In addition, a customer is required to enroll in the Company’s automated payment process in order to enter into a retail installment contract. Subsequent to origination, the Company monitors the delinquency status of retail installment contract receivables as the key credit quality indicator. As of June 30, 2021, the current and delinquent billed retail installment contract receivables were not material. Retail installment contract receivables are recorded at amortized cost less an allowance for credit losses that are not expected to be recovered. The allowance for credit losses on retail installment contract receivables is recognized at inception and reassessed each reporting period.
ADT Contract Assets, Allowance for Credit Loses [Policy Text Block]	The Company records an allowance for credit losses against its contract assets for expected credit losses that are not expected to be recovered. The allowance for credit losses is recognized at inception and reassessed each reporting period.
Contract Liability Policy [Policy Text Block]	Upon initiation of a monitoring contract, the portion of the transaction price associated with the material right is deferred and recorded as deferred subscriber acquisition revenue in the Condensed Consolidated Balance Sheets. Deferred subscriber acquisition revenue is amortized on a pooled basis into installation and other revenue in the Condensed Consolidated Statements of Operations over the estimated life of the customer relationship using an accelerated method consistent with the related amortization of subscriber system assets and deferred subscriber acquisition costs.
contracts with customers, contract assets policy [Policy Text Block]	Contract Assets, netContract assets are recorded when the Company has transferred goods or services to the customer in the ordinary course of business but does not have an unconditional right to such consideration. The contract asset is reclassified to accounts receivable as services are performed and billed, which results in the Company’s unconditional right to the consideration. The Company has the right to bill the customer as service is provided over time, which generally occurs over the course of a 24-, 36-, or 60-month period.
Receivables, Trade and Other Accounts Receivable, Allowance for Doubtful Accounts, Policy	The Company’s allowance for credit losses is evaluated on a pooled basis based on customer type. For each pool of customers, the allowance for credit losses is estimated based on the delinquency status of the underlying receivables and the related historical loss experience, as adjusted for current and expected future conditions, if applicable.

Revenue Revenue (Policies)

6 Months Ended

Jun. 30, 2021

Accounts Receivable, netAccounts receivable represent unconditional rights to consideration due from customers in the ordinary course of business and are generally due in one year or less. Accounts receivable are recorded at amortized cost less an allowance for credit losses that are not expected to be recovered. The allowance for credit losses is recognized at inception and is reassessed each reporting period.

Revenue Outright Sale Policy [Policy Text Block]

In transactions involving systems sold outright to the customer (referred to as outright sales), the Company’s performance obligations generally include the sale and installation of the system as well as any monitoring and related services. For such arrangements, the Company allocates a portion of the transaction price to each performance obligation based on relative standalone selling price, which is determined using observable internal or external pricing and profitability metrics. The portion of the transaction price associated with the sale and installation of a system is recognized either at a point in time or over time based upon the nature of the transaction and contractual terms and is reflected in installation and other revenue in the Condensed Consolidated Statements of Operations. For revenue recognized over time, progress toward complete satisfaction of the performance obligation is primarily measured using a cost-to-cost measure of progress method. The cost input that drives revenue recognition for contracts where revenue is recognized over time is based primarily on contract cost incurred to date compared to total estimated contract cost. This measure of progress method includes forecasts based on the best information available and reflects the Company’s judgment to faithfully depict the value of the services transferred to the customer. The portion of the transaction price associated with monitoring and related services revenue is recognized when services are provided to the customer and is reflected in monitoring and related services revenue in the Condensed Consolidated Statements of Operations.Revenue from product sales related to systems sold under a customer-owned model was $178 million and $259 million for the three months ended June 30, 2021 and 2020, respectively, and $381 million and $553 million for the six months ended June 30, 2021 and 2020, respectively. Cost of revenue from product sales related to systems sold under a customer-owned model was $147 million and $191 million for the three months ended June 30, 2021 and 2020, respectively, and $307 million and $403 million for the six months ended June 30, 2021 and 2020, respectively.

Revenue from Contract with Customer [Policy Text Block]

The Company generates revenue primarily through contractual monthly recurring fees received for monitoring and related services provided to customers. In transactions in which the Company provides monitoring and related services but retains ownership of the security system, the Company’s performance obligations primarily include monitoring, related services (such as maintenance agreements), and a material right associated with the one-time non-refundable fees in connection with the initiation of a monitoring contract that the customer will not be required to pay again upon a renewal of the contract (referred to as deferred subscriber acquisition revenue). The portion of the transaction price associated with monitoring and related services revenue is recognized when the services are provided to the customer and is reflected in monitoring and related services revenue in the Condensed Consolidated Statements of Operations.

Early termination of the contract by the customer results in a termination charge in accordance with the terms of the contract. Contract termination charges are recognized in revenue when collectability is probable and are reflected in monitoring and related services revenue in the Condensed Consolidated Statements of Operations.

The Company records revenue in the Condensed Consolidated Statements of Operations net of sales and other taxes. Amounts collected from customers for sales and other taxes are reported as a liability net of the related amounts remitted.

Customer billings for services not yet rendered are deferred and recognized as revenue as services are provided. These fees are recorded as current deferred revenue in the Condensed Consolidated Balance Sheets as the Company expects to satisfy any remaining performance obligations, as well as recognize the related revenue, within the next twelve months. Accordingly, the Company has applied the practical expedient regarding deferred revenue to exclude the value of remaining performance obligations if (i) the contract has an original expected term of one year or less or (ii) the Company recognizes revenue in proportion to the amount it has the right to invoice for services performed.

Deferred Subscriber Acquisition Costs [Policy Text Block]

Deferred subscriber acquisition costs represent selling expenses (primarily commissions) that are incremental to acquiring customers. Amortization expense relating to deferred subscriber acquisition costs, which is included in selling, general, and administrative expenses in the Condensed Consolidated Statements of Operations was $30 million and $23 million for the three months ended June 30, 2021 and 2020, respectively, and $59 million and $45 million for the six months ended June 30, 2021 and 2020, respectively.

Financing Receivable, Allowance for Credit Losses, Policy for Uncollectible Amounts [Policy Text Block]

Retail Installment Contract Receivables, net

During February 2020, the Company introduced a new retail installment contract option that allows qualifying residential customers to pay the fees due at installation over a 24-, 36-, or 60-month interest-free period. The financing component of the Company’s retail installment contract receivables is not significant.

Retail installment contracts are available for residential transactions occurring under both Company-owned and customer-owned models. When originating a retail installment contract, the Company utilizes external credit scores to assess credit quality of a customer and to determine eligibility for the retail installment contract. In addition, a customer is required to enroll in the Company’s automated payment process in order to enter into a retail installment contract. Subsequent to origination, the Company monitors the delinquency status of retail installment contract receivables as the key credit quality indicator. As of June 30, 2021, the current and delinquent billed retail installment contract receivables were not material.

Retail installment contract receivables are recorded at amortized cost less an allowance for credit losses that are not expected to be recovered. The allowance for credit losses on retail installment contract receivables is recognized at inception and reassessed each reporting period.

ADT Contract Assets, Allowance for Credit Loses [Policy Text Block]

The Company records an allowance for credit losses against its contract assets for expected credit losses that are not expected to be recovered. The allowance for credit losses is recognized at inception and reassessed each reporting period.

Contract Liability Policy [Policy Text Block]

Upon initiation of a monitoring contract, the portion of the transaction price associated with the material right is deferred and recorded as deferred subscriber acquisition revenue in the Condensed Consolidated Balance Sheets. Deferred subscriber acquisition revenue is amortized on a pooled basis into installation and other revenue in the Condensed Consolidated Statements of Operations over the estimated life of the customer relationship using an accelerated method consistent with the related amortization of subscriber system assets and deferred subscriber acquisition costs.

contracts with customers, contract assets policy [Policy Text Block]

Contract Assets, netContract assets are recorded when the Company has transferred goods or services to the customer in the ordinary course of business but does not have an unconditional right to such consideration. The contract asset is reclassified to accounts receivable as services are performed and billed, which results in the Company’s unconditional right to the consideration. The Company has the right to bill the customer as service is provided over time, which generally occurs over the course of a 24-, 36-, or 60-month period.

Receivables, Trade and Other Accounts Receivable, Allowance for Doubtful Accounts, Policy

The Company’s allowance for credit losses is evaluated on a pooled basis based on customer type. For each pool of customers, the allowance for credit losses is estimated based on the delinquency status of the underlying receivables and the related historical loss experience, as adjusted for current and expected future conditions, if applicable.