Discontinued Operations (Narratives) (Details) (Starhome Disposition, USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended		0 Months Ended	6 Months Ended	0 Months Ended
	Jul. 31, 2012	Jul. 31, 2011	Jul. 31, 2012	Jul. 31, 2011	Aug. 01, 2012 Scenario, Forecast Discontinued Operation	Jul. 31, 2011 Scenario, Forecast Discontinued Operation	Aug. 01, 2012 Scenario, Forecast Starhome Discontinued Operation
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net cash proceeds from disposal					$ 37.4		$ 80.3
Cash proceeds held in escrow to cover claims							10.5
First portion of cash proceeds released from escrow							5.5
Period for first portion of cash proceeds held in escrow before release (in months)					18 months
Period for remaining portion of cash proceeds held in escrow before release (in months)					24 months
Payments to certain other shareholders					4.5
Period of noncompete agreement with Starhome (in years)					4 years
Revenue related to insignificant transactions with disposal group	0.9	1.1	2.3	1.7
Cost of revenue related to insignificant transactions with disposal group	$ 0.2	$ 1.2	$ 0.4			$ 1.2