Note 7 - Investment and Advances in Real Estate Joint Ventures (Details) - Summarized Financial Information for RioCan - Balance Sheets (RioCan [Member], USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Schedule of Equity Method Investments [Line Items]
Assets	$ 1,028.1	$ 1,150.0
Members' capital	372.4	393.3
	1,028.1	1,150.0
Real Estate, Net [Member]
Schedule of Equity Method Investments [Line Items]
Assets	987.4	1,106.2
Other Assets [Member]
Schedule of Equity Method Investments [Line Items]
Assets	40.7	43.8
Mortgage Payable [Member]
Schedule of Equity Method Investments [Line Items]
Liabilities	642.6	743.7
Other Liabilities [Member]
Schedule of Equity Method Investments [Line Items]
Liabilities	$ 13.1	$ 13.0