Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Jan. 31, 2015	Apr. 30, 2014	Jan. 31, 2014
Statement of Financial Position [Abstract]
Allowance for doubtful accounts	$ 49,859	$ 52,578	$ 42,716
Allowance for loan losses	9,375	11,272	11,563
Accumulated depreciation and amortization	$ 509,039	$ 446,049	$ 469,733
Common stock, no par value	$ 0us-gaap_CommonStockNoParValue	$ 0us-gaap_CommonStockNoParValue	$ 0us-gaap_CommonStockNoParValue
Common stock, stated value per share	$ 0.01	$ 0.01	$ 0.01
Common stock, shares authorized	800,000,000us-gaap_CommonStockSharesAuthorized	800,000,000us-gaap_CommonStockSharesAuthorized	800,000,000us-gaap_CommonStockSharesAuthorized
Common stock, shares issued	316,628,110us-gaap_CommonStockSharesIssued	316,628,110us-gaap_CommonStockSharesIssued	316,628,110us-gaap_CommonStockSharesIssued
Convertible preferred stock, stated value per share	$ 0.01	$ 0.01	$ 0.01
Convertible preferred stock, shares authorized	500,000us-gaap_PreferredStockSharesAuthorized	500,000us-gaap_PreferredStockSharesAuthorized	500,000us-gaap_PreferredStockSharesAuthorized

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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