CONSOLIDATED STATEMENTS OF CASH FLOWS (unaudited) (Parenthetical) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Apr. 30, 2012	Apr. 30, 2011	Apr. 30, 2010
CASH FLOWS FROM FINANCING ACTIVITIES
Distributions paid to common shareholders, reinvestment	$ 10,177	$ 10,627	$ 9,762
Distributions paid to noncontrolling interests - Unitholders of the Operating Partnership, net reinvestment	$ 657	$ 746	$ 772

The cash inflow from an entity that is affiliated with the entity by means of direct or indirect ownership.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 14

-URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3255-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

-URI http://asc.fasb.org/extlink&oid=6513228

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 18

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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Balance Type:	debit
Period Type:	duration