Commitments and Contingencies (Future Minimum Lease Commitments) (Details) $ in Millions	Mar. 31, 2018 USD ($)
Operating leases
Total	$ 13,002
Fiscal Year 2018	2,205
Fiscal Year 2019	2,147
Fiscal Year 2020	2,035
Fiscal Year 2021	1,739
Fiscal Year 2022	1,198
Fiscal Year 2023 and thereafter	3,678
Spectrum leases and service credits
Total	6,759
Fiscal Year 2018	249
Fiscal Year 2019	272
Fiscal Year 2020	248
Fiscal Year 2021	266
Fiscal Year 2022	262
Fiscal Year 2023 and thereafter	5,462
Purchase orders and other commitments
Total	11,068
Fiscal Year 2018	7,732
Fiscal Year 2019	1,029
Fiscal Year 2020	565
Fiscal Year 2021	393
Fiscal Year 2022	235
Fiscal Year 2023 and thereafter	1,114
Total future minimum commitments
Total	30,829
Fiscal Year 2018	10,186
Fiscal Year 2019	3,448
Fiscal Year 2020	2,848
Fiscal Year 2021	2,398
Fiscal Year 2022	1,695
Fiscal Year 2023 and thereafter	$ 10,254

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No definition available.

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No definition available.

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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 10
-Section 55
-Paragraph 40
-Subparagraph (Note 3)
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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Minimum amount of other commitment not otherwise specified in the taxonomy. Excludes commitments explicitly modeled in the 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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+ References

No definition available.

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No definition available.

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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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No definition available.

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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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No definition available.

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No definition available.

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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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No definition available.

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