Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Apr. 30, 2015	Apr. 30, 2014
Statement of Financial Position [Abstract]
Allowance for doubtful accounts	$ 54,527	$ 52,578
Allowance for loan losses	7,886	11,272
Accumulated depreciation and amortization	$ 518,797	$ 446,049
Common stock, no par value	$ 0us-gaap_CommonStockNoParValue	$ 0us-gaap_CommonStockNoParValue
Common stock, stated value per share	$ 0.01	$ 0.01
Common stock, shares authorized	800,000,000us-gaap_CommonStockSharesAuthorized	800,000,000us-gaap_CommonStockSharesAuthorized
Common stock, shares issued	316,628,110us-gaap_CommonStockSharesIssued	316,628,110us-gaap_CommonStockSharesIssued

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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Face amount per share of no-par value common stock.

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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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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