Schedule Of Deferred Tax Assets (Liabilities) (Detail) (USD $) In Millions, unless otherwise specified	Jan. 30, 2015	Jul. 31, 2014	Jan. 31, 2014
Income Tax Disclosure [Abstract]
Accrued vacation and bonuses	$ 44		$ 62
Investments	3		3
Deferred compensation	39		38
Vesting stock awards	28		34
Credits and net operating losses carryovers	9		27
Employee benefit contributions	4		3
Capital loss carryover	113		0
Reserves	41		51
Deferred rent and tenant allowances	15		14
Other	15us-gaap_DeferredTaxAssetsOther		9us-gaap_DeferredTaxAssetsOther
Total deferred tax assets	311us-gaap_DeferredTaxAssetsGross	27us-gaap_DeferredTaxAssetsGross	241us-gaap_DeferredTaxAssetsGross
Valuation allowance	(120)		(7)
Deferred tax assets, net of valuation allowance	191us-gaap_DeferredTaxAssetsNet		234us-gaap_DeferredTaxAssetsNet
Deferred revenue	(47)		(31)
Fixed asset basis differences	0		(27)
Purchased intangible assets	(121)		(138)
Deferred Tax Liabilities, Partnership Interest	(10)		0
Other	(8)us-gaap_DeferredTaxLiabilitiesOther		0us-gaap_DeferredTaxLiabilitiesOther
Total deferred tax liabilities	(186)us-gaap_DeferredIncomeTaxLiabilities		(196)us-gaap_DeferredIncomeTaxLiabilities
Net deferred tax assets	$ 5us-gaap_DeferredTaxAssetsLiabilitiesNet		$ 38us-gaap_DeferredTaxAssetsLiabilitiesNet

Deferred Tax Assets, Tax Credit and Net Operating Loss Carryforwards

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Deferred Tax Liabilities, Partnership Interest

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Amount of deferred tax liability attributable to taxable temporary differences.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible capital loss carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from the entity's investment in its wholly-owned subsidiaries.

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Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards, net of deferred tax liability attributable to taxable temporary differences.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences not separately disclosed.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from compensated absences (includes, but not limited to, sick and personal days).

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The tax effect as of the balance sheet date of the amount of the estimated future tax deductions arising from employee benefit costs not otherwise specified in the taxonomy, which can only be deducted for tax purposes when actual costs are incurred, and which can only be realized if sufficient tax-basis income is generated in future periods to enable the deduction to be taken.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from employee compensation.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from share-based compensation.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from deferred rent.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from loss reserves other than estimated credit losses.

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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Amount of deferred tax liability attributable to taxable temporary differences from intangible assets other than goodwill.

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Amount of deferred tax liability attributable to taxable temporary differences not separately disclosed.

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Amount of deferred tax liability attributable to taxable temporary differences from property, plant, and equipment.

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Amount of deferred tax liability attributable to taxable temporary differences from tax deferred revenue or other income not separately disclosed.

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