Debt Instrument, Variable Rate On Which Basis Spread Is Calculated, Floor

No definition available.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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- Definition

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.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Face (par) amount of the original debt instrument that was repurchased.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 50
-Section 40
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=49170532&loc=d3e12317-112629

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 50
-Section 40
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=49170532&loc=d3e12355-112629

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Details

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- Details

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- Details

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- Details

Name:	us-gaap_DebtInstrumentAxis=adt_RevolvingCreditFacilityMaturingonMarch162023Member
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- Details

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- Details

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- Details

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- Details

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Debt (Details) - USD ($)		3 Months Ended
Debt (Details) - USD ($)	Feb. 21, 2018	Mar. 31, 2018	Mar. 31, 2017	Mar. 15, 2018
Debt Instrument [Line Items]
Loss on extinguishment of debt		$ 61,597,000	$ 900,000
2021 Revolving Credit Facility \| Revolving Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity				$ 255,000,000
2020 Revolving Credit Facility \| Revolving Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity				$ 95,000,000
2023 Revolving Credit Facility \| Revolving Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity		350,000,000
Remaining borrowing capacity		$ 350,000,000
2023 Revolving Credit Facility \| Revolving Credit Facility \| Federal Funds Effective Swap Rate
Debt Instrument [Line Items]
Variable rate on which basis spread is calculated		0.50%
2023 Revolving Credit Facility \| Revolving Credit Facility \| London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Variable rate on which basis spread is calculated		1.00%
Basis spread on variable rate		2.75%
2023 Revolving Credit Facility \| Revolving Credit Facility \| Base Rate
Debt Instrument [Line Items]
Basis spread on variable rate		1.75%
2023 Revolving Credit Facility \| Revolving Credit Facility \| Minimum
Debt Instrument [Line Items]
Commitment fee percentage		0.375%
2023 Revolving Credit Facility \| Revolving Credit Facility \| Maximum
Debt Instrument [Line Items]
Commitment fee percentage		0.50%
Prime Notes \| Senior Notes
Debt Instrument [Line Items]
Repurchased face amount	$ 594,000,000
Loss on extinguishment of debt	$ 62,000,000