Balance Sheet Details (Narrative) (Details) - USD ($) $ in Millions |
3 Months Ended | 6 Months Ended | ||||||
|---|---|---|---|---|---|---|---|---|
Sep. 30, 2016 |
Sep. 30, 2015 |
Sep. 30, 2016 |
Sep. 30, 2015 |
Mar. 31, 2016 |
[1] | |||
| Balance Sheet Related Disclosures [Abstract] | ||||||||
| Depreciation expense | $ 28 | $ 30 | $ 57 | $ 60 | ||||
| Deferred Revenue, Current | $ 1,067 | $ 1,067 | $ 1,458 | |||||
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