Accumulated other Comprehensive Income (Tables)
 12 Months Ended
Mar. 31, 2015
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]  
Components of Accumulated Other Comprehensive Income (Loss) [Table Text Block]
fiscal years ended March 31, 2015, 2014 and 2013 are as follows (in millions):

 
Unrealized Net Gains (Losses) on Available-for-Sale Securities
 
Unrealized Net Gains (Losses) on Derivative Instruments
 
Foreign Currency Translation Adjustments
 
Total
Balances as of March 31, 2012
$
83

 
$
(2
)
 
$
92

 
$
173

Other comprehensive loss before reclassifications
(46
)
 
(2
)
 
(19
)
 
(67
)
Amounts reclassified from accumulated other comprehensive income
(41
)
 
4

 
—

 
(37
)
Net current-period other comprehensive income (loss)
(87
)
 
2

 
(19
)
 
(104
)
Balances as of March 31, 2013
$
(4
)
 
$
—

 
$
73

 
$
69

Other comprehensive loss before reclassifications
$
—

 
$
(19
)
 
$
(22
)
 
$
(41
)
Amounts reclassified from accumulated other comprehensive income
—

 
9

 
—

 
9

Net current-period other comprehensive income (loss)
—

 
(10
)
 
(22
)
 
(32
)
Balances as of March 31, 2014
(4
)
 
(10
)
 
51

 
37

Other comprehensive income (loss) before reclassifications
$
1

 
$
20

 
$
(67
)
 
$
(46
)
Amounts reclassified from accumulated other comprehensive income
—

 
11

 
—

 
11

Net current-period other comprehensive income (loss)
1

 
31

 
(67
)
 
(35
)
Balances as of March 31, 2015
(3
)
 
21

 
(16
)
 
2
Reclassification out of Accumulated Other Comprehensive Income [Table Text Block]
The effects on net income (loss) of amounts reclassified from accumulated other comprehensive income (loss) for the fiscal years ended March 31, 2015, 2014 and 2013 were as follows (in millions):
 Statement of Operations Classification
 
Amount Reclassified From Accumulated Other Comprehensive Income (loss)
Year Ended March 31,
2015
 
2014
 
2013
Gains and losses on available-for-sale securities
 
 
 
 
 
 
Gains on strategic investments
 
$
—

 
$
—

 
$
(39
)
Interest and other income (expense), net
 
—

 
—

 
(2
)
Net of tax
 
—

 
—

 
(41
)
 
 
 
 
 
 
 
Gains and losses on cash flow hedges from forward contracts
 
 
 
 
 
 
Net revenue
 
(2
)
 
7

 
3

Research and development
 
13

 
2

 
1

Net of tax
 
11

 
9

 
4

 
 
 
 
 
 
 
Total amount reclassified, net of tax
 
$
11

 
$
9

 
$
(37
)