Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease obligations.

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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

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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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Amount, after accumulated amortization, of debt discount (premium).

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Amount of long-term debt and capital lease obligation due after one year or beyond the normal operating cycle, if longer.

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Amount of long-term debt and capital leases due within one year or the normal operating cycle, if longer.

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The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a rate subject to change from time to time.

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The net book value of the asset(s) sold in connection with the sale of the property to another party and lease back to the seller.

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Amount of cash inflow after closing and debt issuance costs received by a seller-lessee in a sale-leaseback recognized in financing activities.

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Long-Term Debt, Financing and Capital Lease Obligations (Schedule of Long-term Debt Instruments) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Dec. 31, 2016	Dec. 01, 2016	Oct. 31, 2016	Dec. 31, 2015	Jul. 10, 2013
Debt Instrument [Line Items]
Debt Instrument, Unamortized Premium (Discount), Net	$ 597	$ 183
Current and Long-term Debt, Financing and Capital Lease Obligations	33,958	37,313
Long Term Debt Financing And Capital Lease Obligations, Current portion	(4,690)	(6,554)
Long-term debt, financing and capital lease obligations	29,268	30,759
Sale Leaseback Transaction, Net Book Value	1,200	447			$ 1,300
Sale Leaseback Transaction, Net Proceeds, Financing Activities	600
Senior Notes [Member] \| Sprint Corporation [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	10,500	10,500
Senior Notes [Member] \| Sprint Nextel Corporation [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			6.00%
Long-term Debt, Gross	9,280	7,280
Senior Notes [Member] \| Sprint Capital Corporation [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	6,204	6,204
Guaranteed notes [Member] \| Sprint Nextel Corporation [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	4,000	$ 4,000
Secured notes [Member] \| Clearwire Communications LLC [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			14.75%
Secured Debt [Member] \| Sprint Spectrum Co LLC, Sprint Spectrum Co II LLC, Sprint Spectrum Co III LLC [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		3.36%		3.36%
Long-term Debt, Gross	0	$ 3,500
Secured Debt [Member] \| Clearwire Communications LLC [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	300	$ 0
Exchangeable notes [Member] \| Clearwire Communications LLC [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		8.25%				8.25%
Long-term Debt, Gross	629	$ 629
Revolving Credit Facility [Member] \| Unsecured Revolving Credit Facility expires in 2018 [Member]
Debt Instrument [Line Items]
Long-term Debt, Percentage Bearing Variable Interest, Percentage Rate		4.00%
Line of Credit Facility, Amount Outstanding	0	$ 0
Line of Credit [Member] \| Export Development Canada Agreement [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Amount Outstanding	550
Line of Credit [Member] \| Secured Equipment Credit Facility [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Amount Outstanding	805	586
Capital Lease Obligations [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 1,093	$ 3,881
Minimum [Member] \| Line of Credit [Member] \| Export Development Canada Agreement [Member]
Debt Instrument [Line Items]
Long-term Debt, Percentage Bearing Variable Interest, Percentage Rate		4.48%
Minimum [Member] \| Line of Credit [Member] \| Secured Equipment Credit Facility [Member]
Debt Instrument [Line Items]
Long-term Debt, Percentage Bearing Variable Interest, Percentage Rate		2.03%
Maximum [Member] \| Line of Credit [Member] \| Export Development Canada Agreement [Member]
Debt Instrument [Line Items]
Long-term Debt, Percentage Bearing Variable Interest, Percentage Rate		6.23%
Maximum [Member] \| Line of Credit [Member] \| Secured Equipment Credit Facility [Member]
Debt Instrument [Line Items]
Long-term Debt, Percentage Bearing Variable Interest, Percentage Rate		3.27%
Successor [Member] \| Minimum [Member] \| Senior Notes [Member] \| Sprint Corporation [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		7.13%
Successor [Member] \| Minimum [Member] \| Senior Notes [Member] \| Sprint Capital Corporation [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		6.88%
Successor [Member] \| Minimum [Member] \| Guaranteed notes [Member] \| Sprint Nextel Corporation [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		7.00%
Successor [Member] \| Minimum [Member] \| Capital Lease Obligations [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		2.35%
Successor [Member] \| Maximum [Member] \| Senior Notes [Member] \| Sprint Corporation [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	7.88%
Successor [Member] \| Maximum [Member] \| Senior Notes [Member] \| Sprint Nextel Corporation [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		11.50%
Successor [Member] \| Maximum [Member] \| Senior Notes [Member] \| Sprint Capital Corporation [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		8.75%
Successor [Member] \| Maximum [Member] \| Guaranteed notes [Member] \| Sprint Nextel Corporation [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		9.00%
Successor [Member] \| Maximum [Member] \| Capital Lease Obligations [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		10.63%