Funding Sources Spectrum Financing (Details) - USD ($) $ in Billions	1 Months Ended
Oct. 31, 2016	Dec. 31, 2016
Secured Debt [Member] \| Sprint Spectrum Co LLC, Sprint Spectrum Co II LLC, Sprint Spectrum Co III LLC [Member]
Debt Instrument [Line Items]
Debt instrument face amount	$ 3.5
Debt Instrument, Interest Rate, Stated Percentage	3.36%	3.36%
Debt Instrument, Term	5 years
Secured Debt [Member] \| Spectrum Financing [Member]
Debt Instrument [Line Items]
Debt Instrument, Maximum Borrowing Capacity	$ 7.0
Debt Instrument, Additional Borrowings Available	3.5
Unsecured Debt [Member] \| Financing Facility [Member]
Debt Instrument [Line Items]
Debt Instrument, Repurchased Face Amount	$ 2.5
Spectrum Assets [Member]
Debt Instrument [Line Items]
Concentration Risk, Percentage	14.00%

Debt Instrument, Additional Borrowings Available

No definition available.

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- Definition

Debt Instrument, Maximum Borrowing Capacity

+ References

No definition available.

+ Details

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
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-Name Accounting Standards Codification
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-Name Accounting Standards Codification
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-Subparagraph (a)
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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
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-Section 45
-Paragraph 2
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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
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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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- Definition

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

+ References

No definition available.

+ Details

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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