Long-term debt (Tables)

3 Months Ended

Apr. 26, 2015

Debt Disclosure [Abstract]

Schedule of Long-term Debt Instruments [Table Text Block]

	April 26,			January 25,
	2015			2015
	(In millions)
Amount of the equity component	$	126		$	126
1.00% Convertible Senior Notes Due 2018	$	1,500		$	1,500
Unamortized debt discount (1)	(109		)	(116		)
Net carrying amount	$	1,391		$	1,384

(1) As of April 26, 2015, the unamortized debt discount will be amortized over a remaining period of 3.6 years.

The following table presents interest expense for the contractual interest and the accretion of debt discount and issuance costs:

	Three Months Ended
	April 26,		April 27,
	2015		2014
	(In millions)
Contractual coupon interest expense	$	4	$	4
Amortization of debt discount and issuance costs	7		7
Total interest expense related to Notes	$	11	$	11