Annual report pursuant to Section 13 and 15(d)

Investments in Marketable Securities (Details 2)

v2.4.0.6
Investments in Marketable Securities (Details 2) (USD $)
In Thousands, unless otherwise specified
Jan. 31, 2013
Jan. 31, 2012
Amortized Cost $ 119,911 $ 92,492
Gross Unrealized Gains 83 88
Gross Unrealized Losses 0 0
Estimated Fair Value 119,994 92,580
Cash [Member]
   
Amortized Cost 104,109 74,226
Gross Unrealized Gains 0 0
Gross Unrealized Losses 0 0
Estimated Fair Value 104,109 74,226
Cash Equivalents [Member]
   
Amortized Cost 2,612 6,359
Gross Unrealized Gains 0 0
Gross Unrealized Losses 0 0
Estimated Fair Value 2,612 6,359
Cash and Cash Equivalents [Member]
   
Amortized Cost 106,721 80,585
Gross Unrealized Gains 0 0
Gross Unrealized Losses 0 0
Estimated Fair Value 106,721 80,585
Us Government Agency Issues Short Term [Member]
   
Amortized Cost 6,043 6,781
Gross Unrealized Gains 61 68
Gross Unrealized Losses 0 0
Estimated Fair Value 6,104 6,849
Us Government Agency Issues Long Term [Member]
   
Amortized Cost 7,147 4,126
Gross Unrealized Gains 22 14
Gross Unrealized Losses 0 0
Estimated Fair Value 7,169 4,140
Corporate Debt Securities Short Term [Member]
   
Amortized Cost 0 1,000
Gross Unrealized Gains 0 6
Gross Unrealized Losses 0 0
Estimated Fair Value 0 1,006
Corporate Debt Securities Long Term [Member]
   
Amortized Cost 0 0
Gross Unrealized Gains 0 0
Gross Unrealized Losses 0 0
Estimated Fair Value 0 0
Marketable Securities Short Term [Member]
   
Amortized Cost 6,043 7,781
Gross Unrealized Gains 61 74
Gross Unrealized Losses 0 0
Estimated Fair Value 6,104 7,855
Marketable Securities Long Term [Member]
   
Amortized Cost 7,147 4,126
Gross Unrealized Gains 22 14
Gross Unrealized Losses 0 0
Estimated Fair Value $ 7,169 $ 4,140