Debt (Stated Rates) (Details)	Jan. 30, 2016	Jan. 31, 2015	Sep. 30, 2014
Series A Unsecured Senior Notes [Member]
Debt Instrument [Line Items]
Unsecured senior notes interest rate	6.38%
Series A Unsecured Senior Notes [Member] | Senior Notes due 2018 [Member]
Debt Instrument [Line Items]
Unsecured senior notes interest rate	6.38%	6.38%
Series B Unsecured Senior Notes [Member]
Debt Instrument [Line Items]
Unsecured senior notes interest rate	6.53%
Series B Unsecured Senior Notes [Member] | Senior Notes due 2021 [Member]
Debt Instrument [Line Items]
Unsecured senior notes interest rate	6.53%	6.53%
Senior Notes [Member]
Debt Instrument [Line Items]
Unsecured senior notes interest rate			3.375%
Senior Notes [Member] | Senior Notes due 2024 [Member]
Debt Instrument [Line Items]
Unsecured senior notes interest rate	3.375%	3.375%