Fair Value Measurement Financial Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) (Fair Value, Measurements, Recurring [Member], USD $) In Thousands, unless otherwise specified	Jan. 31, 2013	Jan. 31, 2012
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Business Acquisition, Contingent Consideration, Potential Cash Payment	$ 6,016	$ 6,120
Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Business Acquisition, Contingent Consideration, Potential Cash Payment	0	0
Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Business Acquisition, Contingent Consideration, Potential Cash Payment	0	0
Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Business Acquisition, Contingent Consideration, Potential Cash Payment	$ 6,016	$ 6,120