Fair Value (Details) - Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation (USD $) In Thousands, unless otherwise specified	6 Months Ended
Jul. 31, 2013	Apr. 30, 2013	Jan. 31, 2013
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Abstract]
Balance	$ 262	$ 252	$ 252
Current period activity	$ 10

Amount of increase (decrease) of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258

Name:	us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPeriodIncreaseDecrease
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	duration