Income Taxes (Narrative) (Details) (USD $)	3 Months Ended								12 Months Ended
	Apr. 30, 2014	Jan. 31, 2014	Oct. 31, 2013	Jul. 31, 2013	Apr. 30, 2013	Jan. 31, 2013	Oct. 31, 2012	Jul. 31, 2012	Apr. 30, 2014	Apr. 30, 2013	Apr. 30, 2012	Apr. 30, 2011
Operating Loss Carryforwards [Line Items]
Net loss from discontinued operations, net of tax benefits of $15,422, $19,662 and $74,944	$ 19,135,000	$ 1,960,000	$ 1,928,000	$ 1,917,000	$ 24,582,000	$ 793,000	$ 4,044,000	$ 1,791,000	$ 24,940,000	$ 31,210,000	$ 80,036,000
Discontinued Operation, Tax Effect of Operations of Discontinued Operation									15,422,000	19,662,000	74,944,000
Deferred tax asset	219,355,000				229,332,000				219,355,000	229,332,000
Unrecognized Tax Benefits, Increase Resulting from Prior Period Tax Positions									9,207,000	1,549,000	1,461,000
Unrecognized tax benefit	111,491,000				146,391,000				111,491,000	146,391,000	206,393,000	154,848,000
Unrecognized tax benefits that would impact effective tax rate	73,700,000				95,300,000				73,700,000	95,300,000	150,400,000
Effect of anticipated settlements of audit issues and expiring statutes of limitations	5,000,000								5,000,000
Total gross interest and penalties accrued	24,600,000				31,700,000				24,600,000	31,700,000	38,600,000
Valuation allowance	19,200,000				54,600,000				19,200,000	54,600,000
Valuation Allowance, Deferred Tax Asset, Change in Amount									35,400,000
Statutory federal tax rate									35.00%	35.00%	35.00%
Settlement reducing uncertain tax benefits									(23,993,000)	(25,259,000)	(8,742,000)
Income Taxes Receivable					151,300,000					151,300,000
Deferred Tax Liability Not Recognized, Amount of Unrecognized Deferred Tax Liability, Undistributed Earnings of Foreign Subsidiaries	10,000,000								10,000,000
Ameriprise
Operating Loss Carryforwards [Line Items]
Deferred tax asset					45,800,000					45,800,000
State And Local Jurisdiction
Operating Loss Carryforwards [Line Items]
Deferred tax asset	21,400,000								21,400,000
Valuation allowance	15,100,000								15,100,000
Settlement reducing uncertain tax benefits									(6,692,000)
Internal Revenue Service (IRS) [Member]
Operating Loss Carryforwards [Line Items]
Settlement reducing uncertain tax benefits									$ (17,301,000)