Income Taxes (Narrative) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2012	Dec. 31, 2011
Income Tax Footnote Disclosure [Line Items]
Effective tax rates	36.40%	6.20%	17.80%	5.50%
United States statutory tax rate	35.00%	35.00%	35.00%	35.00%
Effective tax rate for non-U.S. profits			0.00%	0.00%
Unrecognized Tax Benefits, Period Increase (Decrease)	$ 5
Gross unrecognized tax benefits	288		288
Cash deposits to offset uncertain tax liabilities	46		46
Amount of unrecognized tax benefits that would affect the effective tax rate	106		106
The total amount of unrecognized tax benefits that, if recognized, would result in adjustments to deferred tax assets with corresponding adjustments to the valuation allowance	170		170
Unrecognized Tax Benefits Income Tax Penalties And Interest Accrued Increase Decrease	1
Combined amount of accrued interest and penalties related to uncertain tax positions	24		24
Popcap Entity And Klick Nation Entity [Member]
Income Tax Footnote Disclosure [Line Items]
Net deferred tax liabilities		3		58
Popcap Entity And Klick Nation Entity [Member] | Valuation Allowance Release [Member]
Income Tax Footnote Disclosure [Line Items]
Net deferred tax liabilities		3		58
Maximum
Income Tax Footnote Disclosure [Line Items]
Amount of unrecognized tax benefits for which it is reasonably possible that there will be a reduction within the next 12 months	$ 84		$ 84