Fair Value Fair Value (Summary Of Carrying Amounts And Estimated Fair Values Of Company's Financial Instruments) (Details) - USD ($) $ in Thousands	Oct. 31, 2016	Apr. 30, 2016	Oct. 31, 2015	Apr. 30, 2015
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Cash & cash equivalents	$ 232,510	$ 896,801	$ 360,681	$ 2,007,190
Cash and cash equivalents, Estimated Fair Value	232,510	896,801
Cash and cash equivalents - restricted, Carrying Amount	109,538	104,110	42,781
Cash and cash equivalents - restricted, Estimated Fair Value	109,538	104,110
Receivables, net	104,764	153,116	94,760
Receivables, net - short-term, Estimated Fair Value	104,764	153,116
Mortgage loans held for investment, less allowance for loan losses of $ - , $7,412 and $5,518		202,385	220,671
Loans Receivable, Fair Value Disclosure	0	190,503
Accounts Receivable, Net, Noncurrent	56,238	60,407	75,275
Receivables, net - long-term, Estimated Fair Value	56,238	60,407	75,275
Total Portfolio	187,057	206,208	226,224
Long-term Debt	1,968,109	1,492,201
Long-term borrowings, Estimated Fair Value	2,067,234	1,566,098
Contingent consideration payments, carrying amount	7,817	8,657
Contingent consideration payments, estimated fair value	$ 7,817	$ 8,657
Level 1
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Cash and cash equivalents, Estimated Fair Value			360,681
Cash and cash equivalents - restricted, Estimated Fair Value			42,781
Receivables, net - short-term, Estimated Fair Value			94,760
Level 3
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Loans Receivable, Fair Value Disclosure			180,437
Long-term Debt			1,491,322
Long-term borrowings, Estimated Fair Value			1,553,633
Contingent consideration payments, carrying amount			11,932
Contingent consideration payments, estimated fair value			$ 11,932