Other Balance Sheet Accounts - Schedule of Capitalized Software Costs (Detail) (USD $) In Thousands, unless otherwise specified	Oct. 31, 2014	Jan. 31, 2014
Property, Plant and Equipment [Line Items]
Capitalized software costs	$ 448,088	$ 481,917
Capitalized internal-use software development costs, net of accumulated amortization of $127,842 and $101,687, respectively
Property, Plant and Equipment [Line Items]
Capitalized software costs	89,106	72,915
Accumulated amortization	127,842	101,687
Acquired developed technology, net of accumulated amortization of $370,535 and $294,628, respectively
Property, Plant and Equipment [Line Items]
Capitalized software costs	358,982	409,002
Accumulated amortization	$ 370,535	$ 294,628