|
Changes in Accumulated Other Comprehensive Income by Component (Details) (USD $)
In Millions, unless otherwise specified
|
12 Months Ended |
|
Mar. 31, 2015
|
Mar. 31, 2014
|
Mar. 31, 2013
|
| Accumulated Other Comprehensive Income (Loss) [Roll Forward] |
|
|
|
| Beginning Balance |
$ 37 |
$ 69 |
$ 173 |
| Other comprehensive income (loss) before reclassifications |
(46) |
(41) |
(67) |
| Amounts reclassified from accumulated other comprehensive income |
11 |
9 |
(37) |
| Net current-period other comprehensive income (loss) |
(35) |
(32) |
(104) |
| Ending balance |
2 |
37 |
69 |
| Unrealized Gains (Losses) on Available-for-Sale Securities [Member] |
|
|
|
| Accumulated Other Comprehensive Income (Loss) [Roll Forward] |
|
|
|
| Beginning Balance |
(4) |
(4) |
83 |
| Other comprehensive income (loss) before reclassifications |
1 |
0 |
(46) |
| Amounts reclassified from accumulated other comprehensive income |
0 |
0 |
(41) |
| Net current-period other comprehensive income (loss) |
1 |
0 |
(87) |
| Ending balance |
(3) |
(4) |
(4) |
| Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member] |
|
|
|
| Accumulated Other Comprehensive Income (Loss) [Roll Forward] |
|
|
|
| Beginning Balance |
(10) |
0 |
(2) |
| Other comprehensive income (loss) before reclassifications |
20 |
(19) |
(2) |
| Amounts reclassified from accumulated other comprehensive income |
11 |
9 |
4 |
| Net current-period other comprehensive income (loss) |
31 |
(10) |
2 |
| Ending balance |
21 |
(10) |
0 |
| Foreign Currency Translation Adjustment [Member] |
|
|
|
| Accumulated Other Comprehensive Income (Loss) [Roll Forward] |
|
|
|
| Beginning Balance |
51 |
73 |
92 |
| Other comprehensive income (loss) before reclassifications |
(67) |
(22) |
(19) |
| Amounts reclassified from accumulated other comprehensive income |
0 |
0 |
0 |
| Net current-period other comprehensive income (loss) |
(67) |
(22) |
(19) |
| Ending balance |
$ (16) |
$ 51 |
$ 73 |