Fair Value Measurements (Tables)

12 Months Ended

Jan. 31, 2014

Fair Value Disclosures [Abstract]

Fair Value Hierarchy for Financial Assets Measured at Fair Value on Recurring Basis

The following table presents the fair value hierarchy for financial assets measured at fair value on a recurring basis as of January 31, 2014 (in thousands):

	Level 1		Level 2		Level 3		Total
Cash equivalents:
Money market funds	$	170,235	$	—	$	—	$	170,235
Commercial paper		—		9,999		—		9,999
U.S. treasury securities		—		33,154		—		33,154
Short-term investments
Corporate notes and bonds		—		10,507		—		10,507
U.S. agency obligations		—		15,117		—		15,117
Total	$	170,235	$	68,777	$	—	$	239,012

The following table presents the fair value hierarchy for financial assets measured at fair value on a recurring basis as of January 31, 2013 (in thousands):

	Level 1		Level 2		Level 3		Total
Cash equivalents:
Money market funds	$	7,637	$	—	$	—	$	7,637
Short-term investments
Commercial paper		—		2,097		—		2,097
Corporate notes and bonds		—		11,479		—		11,479
Certificate of deposits		—		700		—		700
Total	$	7,637	$	14,276	$	—	$	21,913