v3.5.0.1

Acquisitions (Details) - USD ($) $ in Millions | 6 Months Ended
--- | ---
Mar. 31, 2016 | Mar. 27, 2015
Business Combinations [Abstract] |  |
Payments For Dealer Generated Customer Accounts And Non Dealer Bulk Account Purchases | $ 282 | $ 267

X
- Definition The cash outflow associated with the purchase of customer accounts from third parties. + References No definition available. + Details
Name: | adt_PaymentsForDealerGeneratedCustomerAccountsAndNonDealerBulkAccountPurchases
Namespace Prefix: | adt_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_BusinessCombinationsAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration