Quarterly report pursuant to Section 13 or 15(d)

Fair Value Measurements (Details 3)

v2.4.0.6
Fair Value Measurements (Details 3) (USD $)
In Thousands, unless otherwise specified
Oct. 31, 2012
Jan. 31, 2012
Cost $ 97,779 $ 92,492
Gross Unrealized Gains 67 88
Gross Unrealized Losses 0 0
Estimated Fair Value 97,846 92,580
Cash [Member]
   
Cost 81,969 74,226
Gross Unrealized Gains 0 0
Gross Unrealized Losses 0 0
Estimated Fair Value 81,969 74,226
Cash equivalents [Member]
   
Cost 3,089 6,359
Gross Unrealized Gains 0 0
Gross Unrealized Losses 0 0
Estimated Fair Value 3,089 6,359
Cash and cash equivalents [Member]
   
Cost 85,058 80,585
Gross Unrealized Gains 0 0
Gross Unrealized Losses 0 0
Estimated Fair Value 85,058 80,585
Us Government Agency Issues Short Term [Member]
   
Cost 2,004 6,781
Gross Unrealized Gains 41 68
Gross Unrealized Losses 0 0
Estimated Fair Value 2,045 6,849
Corporate debt securities [Member]
   
Cost 0 1,000
Gross Unrealized Gains 0 6
Estimated Fair Value 0 1,006
Marketable securities-short-term [Member]
   
Cost 2,004 7,781
Gross Unrealized Gains 41 74
Gross Unrealized Losses 0 0
Estimated Fair Value 2,045 7,855
Us Government Agency Issues Long Term [Member]
   
Cost 10,717 4,126
Gross Unrealized Gains 26 14
Gross Unrealized Losses 0 0
Estimated Fair Value 10,743 4,140
Marketable securities - long-term [Member]
   
Cost 10,717 4,126
Gross Unrealized Gains 26 14
Gross Unrealized Losses 0 0
Estimated Fair Value $ 10,743 $ 4,140