Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Oct. 31, 2015	Apr. 30, 2015	Oct. 31, 2014
Statement of Financial Position [Abstract]
Treasury Stock, Shares	40,138,877	41,353,479	41,462,487
Allowance for doubtful accounts	$ 53,340	$ 54,527	$ 51,746
Allowance for loan losses	7,412	7,886	9,761
Accumulated depreciation and amortization	$ 563,158	$ 518,797	$ 491,153
Common stock, no par value	$ 0	$ 0	$ 0
Common stock, stated value per share	$ 0.01	$ 0.01	$ 0.01
Common stock, shares authorized	800,000,000	800,000,000	800,000,000
Common stock, shares issued	276,087,566	316,628,110	316,628,110