Acquisitions of and Investments in Businesses and Technologies (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Apr. 30, 2013	Apr. 30, 2012	Apr. 30, 2012 Ranchview [Member]	Nov. 30, 2009 Ranchview [Member]
Business Acquisition [Line Items]
Contingent consideration, potential cash payment				$ 4,000
Contingent consideration, cash paid to settle			1,841
Gain on acquisition-related contingent liability settlement	$ 0	$ (508)	$ 508

Amount of potential cash payments that could result from the contingent consideration arrangement.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 51

-Subparagraph f

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Name:	us-gaap_BusinessAcquisitionContingentConsiderationPotentialCashPayment
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant