Income Taxes 4 (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Deferred tax assets:
Share-based compensation	$ 31	$ 30
Accrued expenses	36	36
Net operating losses	96	131
Total deferred tax assets	604us-gaap_DeferredTaxAssetsGross	659us-gaap_DeferredTaxAssetsGross
Valuation allowances	(85)	(87)
Total deferred tax assets, net of valuation allowance	519us-gaap_DeferredTaxAssetsNet	572us-gaap_DeferredTaxAssetsNet
Deferred tax liabilities:
Depreciation	3	6
Other intangible assets	17	34
Total deferred tax liabilities	161us-gaap_DeferredTaxLiabilities	274us-gaap_DeferredTaxLiabilities
Net deferred tax asset	358us-gaap_DeferredTaxAssetsLiabilitiesNet	298us-gaap_DeferredTaxAssetsLiabilitiesNet
Modified Accrual Basis Accounting for Revenue
Deferred tax assets:
Deferred tax assets, Other	349	373
Intangible Assets Amortizable for Tax Purposes
Deferred tax assets:
Deferred tax assets, Other	3	4
Deductible State Tax and Interest Benefits
Deferred tax assets:
Deferred tax assets, Other	20	20
Other
Deferred tax assets:
Deferred tax assets, Other	69	65
Purchased Software
Deferred tax liabilities:
Capitalized software	48	76
Internally Developed Software
Deferred tax liabilities:
Capitalized software	$ 93	$ 158

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