Mortgage Loans Held For Investment And Related Assets (Information Related To Activities Of Non-Performing Assets) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Apr. 30, 2013	Apr. 30, 2012	Apr. 30, 2011
Mortgage Loans Held For Investment And Related Assets [Line Items]
Average impaired loans	$ 159,361	$ 245,807	$ 289,755
Interest income on impaired loans	4,130	5,899	6,624
Interest income on impaired loans recognized on a cash basis on non-accrual status	4,025	5,682	6,311
Purchased From SCC
Mortgage Loans Held For Investment And Related Assets [Line Items]
Average impaired loans	133,936	211,867	252,673
Interest income on impaired loans	3,825	5,454	5,795
Interest income on impaired loans recognized on a cash basis on non-accrual status	3,746	5,265	5,567
All Other
Mortgage Loans Held For Investment And Related Assets [Line Items]
Average impaired loans	25,425	33,940	37,082
Interest income on impaired loans	305	445	829
Interest income on impaired loans recognized on a cash basis on non-accrual status	$ 279	$ 417	$ 744