Ratio Of Total Indebtedness To Adjusted EBITDA

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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.

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- Definition

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

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

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The amount for notes payable (written promise to pay), due to related parties.

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Amount of additional paid-in capital (APIC) classified as other.

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The cash inflow from the collection of money previously advanced to an entity that is related to it but not strictly controlled.

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Guarantor Financial Information (Details) $ in Millions	12 Months Ended
Guarantor Financial Information (Details) $ in Millions	Mar. 31, 2017 USD ($)	Mar. 31, 2018 USD ($)	Feb. 20, 2018 USD ($)	Feb. 24, 2015 USD ($)	Dec. 12, 2013 USD ($)	Sep. 11, 2013 USD ($)
Condensed Financial Statements, Captions [Line Items]
Proceeds from Collection of Advance to Affiliate	$ 0
Ratio of total indebtedness to adjusted EBITDA		2.5
Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Proceeds from Collection of Advance to Affiliate	84
Non-Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Proceeds from Collection of Advance to Affiliate	0
Other Additional Capital	450	$ 12,800
Notes Payable, Related Parties		$ 24,400
Parent [Member]
Condensed Financial Statements, Captions [Line Items]
Proceeds from Collection of Advance to Affiliate	0
Sprint Communications Inc. Guaranteed Notes due 2021 [Member] \| Senior Notes [Member]
Condensed Financial Statements, Captions [Line Items]
Debt instrument, face amount			$ 1,500	$ 1,500		$ 2,250
Debt instrument, interest rate, stated percentage				7.625%		7.25%
Sprint Corporation 7.875% [Member] \| Senior Notes [Member]
Condensed Financial Statements, Captions [Line Items]
Debt instrument, face amount						$ 4,250
Debt instrument, interest rate, stated percentage						7.875%
Sprint Corporation 7.125% [Member] [Member] \| Senior Notes [Member]
Condensed Financial Statements, Captions [Line Items]
Debt instrument, face amount					$ 2,500
Debt instrument, interest rate, stated percentage					7.125%
Consolidation, Eliminations [Member]
Condensed Financial Statements, Captions [Line Items]
Proceeds from Collection of Advance to Affiliate	$ (84)