XML 49 R47.htm IDEA: XBRL DOCUMENT v2.4.0.6
Summary of Significant Accounting Policies - Additional Information (Detail) (USD $)
In Thousands, unless otherwise specified
12 Months Ended
Jan. 31, 2012
Jan. 31, 2011
Jan. 31, 2010
Mar. 18, 2010
Significant Accounting Policies [Line Items]        
Cash equivalents $ 39,769 $ 6,000    
Restricted cash held in escrow for the purchase of land $ 4,237      
Interest acquired in joint venture       50.00%
Finance fee, percentage 2.00% 2.00% 1.90%  
Building
       
Significant Accounting Policies [Line Items]        
Property, Plant, and Equipment, useful life 40      
Land Improvements
       
Significant Accounting Policies [Line Items]        
Property, Plant, and Equipment, useful life 20      
Equipment
       
Significant Accounting Policies [Line Items]        
Property, Plant, and Equipment, useful life, minimum 3      
Property, Plant, and Equipment, useful life, maximum 5      
Leasehold Improvements
       
Significant Accounting Policies [Line Items]        
Property, Plant, and Equipment, useful life, minimum 3      
Property, Plant, and Equipment, useful life, maximum 10      
Purchased Technologies
       
Significant Accounting Policies [Line Items]        
Intangible assets, amortization period minimum 3      
Intangible assets, amortization period maximum 5      
Other Intangible Assets
       
Significant Accounting Policies [Line Items]        
Intangible assets, amortization period minimum 1      
Intangible assets, amortization period maximum 5