Components of Long Term Debt (Details) (USD $) In Millions, unless otherwise specified	Jan. 31, 2015	Feb. 01, 2014
Debt Instrument [Line Items]
Unamortized debt discount	$ (7)	$ (8)
Long-term debt	2,793us-gaap_LongTermDebtNoncurrent	2,792us-gaap_LongTermDebtNoncurrent
Senior Notes
Debt Instrument [Line Items]
Effective Rate	5.54%
Total senior debt	2,800	2,800
Senior Notes \| Senior Notes Due 2017
Debt Instrument [Line Items]
Effective Rate	6.31%	6.31%
Total senior debt	650	650
Debt Instrument, Interest Rate, Stated Percentage	6.25%	6.25%
Senior Notes \| Senior Notes Due 2021
Debt Instrument [Line Items]
Effective Rate	4.81%	4.81%
Total senior debt	650	650
Debt Instrument, Interest Rate, Stated Percentage	4.00%	4.00%
Senior Notes \| Senior Notes Due Twenty Twenty Three [Member]
Debt Instrument [Line Items]
Effective Rate	3.25%	3.25%
Total senior debt	350	350
Debt Instrument, Interest Rate, Stated Percentage	3.25%	3.25%
Senior Notes \| Senior Notes Due 2029
Debt Instrument [Line Items]
Effective Rate	7.36%	7.36%
Total senior debt	200	200
Debt Instrument, Interest Rate, Stated Percentage	7.25%	7.25%
Senior Notes \| Senior Notes Due 2033
Debt Instrument [Line Items]
Effective Rate	6.05%	6.05%
Total senior debt	300	300
Debt Instrument, Interest Rate, Stated Percentage	6.00%	6.00%
Senior Notes \| Four Point Seven Eight Percent Senior Note Due Twenty Twenty Three [Member] [Domain]
Debt Instrument [Line Items]
Effective Rate	4.78%	4.78%
Total senior debt	300	300
Debt Instrument, Interest Rate, Stated Percentage	4.75%	4.75%
Senior Notes \| Senior Notes Due 2037
Debt Instrument [Line Items]
Effective Rate	6.89%	6.89%
Total senior debt	$ 350	$ 350
Debt Instrument, Interest Rate, Stated Percentage	6.88%	6.88%

Contractual interest rate for funds borrowed, under the debt agreement.

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

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- Definition

The amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized.

+ References

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Carrying amount of long-term debt, net of unamortized discount or premium, excluding amounts to be repaid within one year or the normal operating cycle, if longer (current maturities). Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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Weighted average interest rate of long-term debt outstanding.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

+ References

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