Investments (Narrative) (Details) (USD $) Share data in Millions, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended			12 Months Ended			3 Months Ended		9 Months Ended		1 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011	Dec. 31, 2011	Jan. 02, 2014 Additional Notes Receivable [Member]	Jan. 02, 2012 Additional Notes Receivable [Member] terms	Nov. 28, 2008 Notes Receivable [Member]	Sep. 30, 2012 Clearwire [Member]	Sep. 30, 2011 Clearwire [Member]	Sep. 30, 2012 Clearwire [Member]	Sep. 30, 2011 Clearwire [Member]	Jun. 30, 2012 Clearwire Class B Voting [Member]	Sep. 30, 2012 Clearwire Class B Voting [Member]	Sep. 30, 2012 Clearwire Class B Non Voting [Member]
Schedule of Equity Method Investments [Line Items]
Sprint share in percentage of non-controlling interest in Clearwire														48.20%	48.20%
Carrying value of non-controlling interest									$ 764,000,000		$ 764,000,000
Equity method investment book value per share									$ 1.08		$ 1.08
Equity Method Investment, Shares Repurchased													78
Common Stock, Par or Stated Value Per Share	$ 2		$ 2		$ 2								$ 0.0001
Equity Method Investment, Stock Repurchased, Value													8,000
Notes Receivable, Related Parties	316,000,000		316,000,000		178,000,000		150,000,000
Interest Rate of Note Receivable, Related Parties							11.50%	12.00%
Number of installments							2
Future payment on notes receivable, related party						75,000,000
Equity in losses from Clearwire									208,000,000	271,000,000	927,000,000	1,300,000,000
Asset Impairment Charges			84,000,000	0						15,000,000	41,000,000	309,000,000
Equity Method Investment, Other than Temporary Impairment			204,000,000
Equity Method Investment, Difference Between Carrying Amount and Underlying Equity	338,000,000		338,000,000
Prepaid Expenses and Other Current Assets, Related Parties	119,000,000		119,000,000		5,000,000
Accounts Payable, Related Parties, Current	155,000,000		155,000,000		77,000,000
Related Party Transaction, Amounts of Transaction	$ 103,000,000	$ 111,000,000	$ 312,000,000	$ 263,000,000