Income Taxes 4 (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2012	Mar. 31, 2011
Deferred tax assets:
Modified accrual basis accounting for revenue	$ 447	$ 441
Share-based compensation	48	50
Accrued expenses	30	53
Net operating losses	173	178
Total deferred tax assets	818	833
Valuation allowances	(68)	(85)
Total deferred tax assets, net of valuation allowances	750	748
Deferred tax liabilities:
Depreciation	31	17
Capitalized development costs	206	191
Total deferred tax liabilities	426	351
Net deferred tax asset	324	397
Purchased Software [Member]
Deferred tax liabilities:
Goodwill and intangible assets	133	73
Other Intangible Assets [Member]
Deferred tax liabilities:
Goodwill and intangible assets	56	70
Intangible Assets Amortizable for Tax Purposes [Member]
Deferred tax assets:
Other	11	16
Deductible State Tax and Interest Benefits [Member]
Deferred tax assets:
Other	56	43
Other [Member]
Deferred tax assets:
Other	$ 53	$ 52