Other Balance Sheet Accounts - Schedule of Other Assets (Detail) (USD $) In Thousands, unless otherwise specified	Oct. 31, 2014	Jan. 31, 2014
Finite-Lived Intangible Assets [Line Items]
Deferred income taxes, noncurrent, net	$ 8,128	$ 9,691
Long-term deposits	19,597	17,970
Strategic investments	132,150	92,489
Customer contract asset	3,747	18,182
Other	71,032	47,082
Other assets, net	595,163	613,490
Purchased intangible assets, net of accumulated amortization of $111,273 and $66,399, respectively
Finite-Lived Intangible Assets [Line Items]
Acquired intangible assets	349,665	416,119
Accumulated amortization	111,273	66,399
Acquired intellectual property, net of accumulated amortization of $14,216 and $11,304, respectively
Finite-Lived Intangible Assets [Line Items]
Acquired intangible assets	10,844	11,957
Accumulated amortization	$ 14,216	$ 11,304