CONSOLIDATED STATEMENTS OF INCOME - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Apr. 30, 2015	Apr. 30, 2014	Apr. 30, 2013
CONSOLIDATED STATEMENTS OF INCOME [Abstract]
Revenue	$ 1,822,440	$ 1,775,195	$ 1,760,778
Costs and Expenses
Cost of sales	499,683	506,879	532,232
Operating and administrative expenses	1,005,000	969,456	933,148
Restructuring charges	28,804	42,722	29,293
Impairment charges	0	4,786	30,679
Amortization of intangibles	51,214	44,679	41,982
Total Costs and Expenses	1,584,701	1,568,522	1,567,334
Net Gain on Sale of Consumer Publishing Programs	0	0	5,983
Operating Income	237,739	206,673	199,427
Interest expense	(17,077)	(13,916)	(13,078)
Foreign exchange transaction gains (losses)	1,742	(8)	(2,041)
Interest income and other	3,057	2,785	2,614
Income Before Taxes	225,461	195,534	186,922
Provision for Income Taxes	48,593	35,024	42,697
Net Income	$ 176,868	$ 160,510	$ 144,225
Earnings Per Share
Diluted (in dollars per share)	$ 2.97	$ 2.70	$ 2.39
Basic (in dollars per share)	$ 3.01	$ 2.73	$ 2.43
Average Shares
Diluted (in shares)	59,594	59,514	60,224
Basic (in shares)	58,733	58,635	59,447
Class A Common [Member]
Cash Dividends Per Share
Common stock (in dollars per share)	$ 1.16	$ 1.00	$ 0.96
Class B Common [Member]
Cash Dividends Per Share
Common stock (in dollars per share)	$ 1.16	$ 1.00	$ 0.96