Lessee, Operating Lease, Lease Not yet Commenced, Payments Due

No definition available.

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Period Type:	instant

- Definition

Operating Lease, Advance Payments

+ References

No definition available.

+ Details

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

- Definition

Right-of-Use Asset Obtained in Exchange for Operating and Finance Lease Liabilities

+ References

No definition available.

+ Details

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Namespace Prefix:	tmus_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of interest paid on finance lease liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (g)(1)
-URI http://asc.fasb.org/extlink&oid=123408670&loc=SL77918686-209980

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 5
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123391704&loc=SL77918643-209977

+ Details

Name:	us-gaap_FinanceLeaseInterestPaymentOnLiability
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Change during the period in carrying value for all deferred liabilities due within one year or operating cycle.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3602-108585

+ Details

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

- Definition

Term of lessee's finance lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=123408670&loc=SL77918673-209980

+ Details

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Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	instant

- 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

Name:	us-gaap_LesseeLeaseDescriptionLineItems
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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Term of lessee's operating lease renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

+ Details

Name:	us-gaap_LesseeOperatingLeaseRenewalTerm
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	instant

- Definition

Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

+ Details

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Balance Type:	na
Period Type:	instant

- Details

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- Details

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Leases - Narrative (Details) - USD ($) $ in Millions		12 Months Ended
Leases - Narrative (Details) - USD ($) $ in Millions	Jan. 03, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Lessee, Lease, Description [Line Items]
Advance payment on operating lease		$ 1,000
Interest payments for financing leases		69	$ 79	$ 82
Additional operating leases not yet commenced, payments due		$ 98
Minimum
Lessee, Lease, Description [Line Items]
Lessee leasing arrangements, operating leases, term of contract (years)		5 years
Lessee, operating lease, renewal term (years)		5 years
Lessee leasing arrangements, finance leases, term of contract		2 years
Minimum \| Subsequent Event
Lessee, Lease, Description [Line Items]
Right-of-use asset obtained in exchange for operating and finance lease liabilities	$ 4,800
Increase to deferred tax liabilities	1,200
Maximum
Lessee, Lease, Description [Line Items]
Lessee leasing arrangements, operating leases, term of contract (years)		15 years
Lessee, operating lease, renewal term (years)		35 years
Lessee leasing arrangements, finance leases, term of contract		5 years
Maximum \| Subsequent Event
Lessee, Lease, Description [Line Items]
Right-of-use asset obtained in exchange for operating and finance lease liabilities	5,400
Increase to deferred tax liabilities	$ 1,400