Commitments and Contingencies (Future Minimum Lease Commitments) (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2015
Operating leases
Total	$ 15,381
2015	2,122
2016	2,078
2017	2,015
2018	1,964
2019	1,857
2020 and thereafter	5,345
Spectrum leases and service credits
Total	6,725us-gaap_OtherCommitment
2015	194
2016	204us-gaap_OtherCommitmentDueInSecondYear
2017	212us-gaap_OtherCommitmentDueInThirdYear
2018	214us-gaap_OtherCommitmentDueInFourthYear
2019	218us-gaap_OtherCommitmentDueInFifthYear
2020 and thereafter	5,683
Purchase orders and other commitments
Total	15,004us-gaap_PurchaseObligation
2015	8,861
2016	2,614
2017	1,147
2018	914
2019	460
2020 and thereafter	1,008
Total future minimum commitments
Total	37,110us-gaap_ContractualObligation
2015	11,177
2016	4,896
2017	3,374
2018	3,092
2019	2,535
2020 and thereafter	$ 12,036

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Amount of contractual obligation, including but not limited to, long-term debt, capital lease obligations, operating lease obligations, purchase obligations, and other commitments.

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Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 20

-Section 50

-Paragraph 2

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6453985&loc=d3e41502-112717

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 10

-Section 55

-Paragraph 40

-Subparagraph (Note 3)

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Minimum amount of other commitment maturing after the fifth fiscal year following the latest fiscal year for commitments not otherwise specified in the taxonomy. Excludes commitments explicitly modeled in this taxonomy, including but not limited to, long-term and short-term purchase commitments, recorded and unrecorded purchase obligations, supply commitments, registration payment arrangements, leases, debt, product warranties, guarantees, environmental remediation obligations, and pensions.

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Minimum amount of purchase arrangement in which the entity has agreed to expend funds to procure goods or services from a supplier.

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Minimum amount of purchase arrangement maturing after the fifth fiscal year following the latest fiscal year. Includes, but not limited to, recorded and unrecorded purchase obligations, long-term purchase commitments, and short-term purchase commitments.

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Minimum amount of purchase arrangement maturing in the next fiscal year following the latest fiscal year. Includes, but not limited to, recorded and unrecorded purchase obligations, long-term purchase commitments, and short-term purchase commitments.

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Minimum amount of purchase arrangement maturing in the second fiscal year following the latest fiscal year. Includes, but not limited to, recorded and unrecorded purchase obligations, long-term purchase commitments, and short-term purchase commitments.

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No definition available.

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Minimum amount of purchase arrangement maturing in the third fiscal year following the latest fiscal year. Includes, but not limited to, recorded and unrecorded purchase obligations, long-term purchase commitments, and short-term purchase commitments.

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