Fair Value Measurements (Details) - Fair Value, Measurements, Recurring [Member] - Estimate of Fair Value [Member] - USD ($) $ in Millions	Jan. 29, 2016	Jan. 30, 2015
Short-term Investments [Member]
Available-for-sale Securities
Fair value	$ 307	$ 125
Short-term Investments [Member] | Money Market Funds [Member] | Fair Value (Level 1) [Member]
Available-for-sale Securities
Fair value	192	81
Short-term Investments [Member] | Certificates of Deposit [Member] | Fair Value (Level 1) [Member]
Available-for-sale Securities
Fair value	56	17
Short-term Investments [Member] | Municipal Obligations [Member] | Fair Value (Level 2) [Member]
Available-for-sale Securities
Fair value	38	21
Short-term Investments [Member] | Municipal Floating Rate Obligations [Member] | Fair Value (Level 2) [Member]
Available-for-sale Securities
Fair value	21	6
Long-term Investments [Member]
Available-for-sale Securities
Fair value	222	354
Long-term Investments [Member] | Certificates of Deposit [Member] | Fair Value (Level 1) [Member]
Available-for-sale Securities
Fair value	5	4
Long-term Investments [Member] | Municipal Obligations [Member] | Fair Value (Level 2) [Member]
Available-for-sale Securities
Fair value	5	2
Long-term Investments [Member] | Municipal Floating Rate Obligations [Member] | Fair Value (Level 2) [Member]
Available-for-sale Securities
Fair value	$ 212	$ 348