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Fair Value Measurements - Additional Information (Detail) (USD $)
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9 Months Ended | |
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Oct. 31, 2013
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Jan. 31, 2013
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| Fair Value Disclosures [Abstract] | ||
| Reclassification of fair value assets from Level 1 to Level 2 | $ 0 | $ 0 |
| Maximum maturity of marketable securities | 3 months |
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- Definition
Maximum maturity period of marketable securities. No definition available.
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- Definition
Amount of transfers of assets measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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