Note 6 - Impairments - Asset Impairment Charges (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Asset Impairment Charges, Total	[1],[2]	$ 79,207	$ 67,331	$ 93,266
Noncontrolling interests				(400)
Benefit for income taxes				(21,100)
Total net impairment charges		79,200	67,300	71,800
Properties Marketed for Sale [Member]
Asset Impairment Charges, Total	[3],[4]	59,500	34,000	28,600
Disposed Operating Properties [Member]
Asset Impairment Charges, Total		19,700	17,100	37,200
Properties Held and Used [Member]
Asset Impairment Charges, Total	[5]		$ 16,200	$ 27,500

[1] During 2016, the Company recognized aggregate impairment charges of $93.3 million, before an income tax benefit of $21.1 million and noncontrolling interests of $0.4 million, primarily related to sale of certain operating properties and certain properties maintained in the Company's TRS for which the hold period was re-evaluated in connection with the Merger (see Footnote 21 of the Notes to Consolidated Financial Statements for additional disclosure) and adjustments to property carrying values in connection with the Company's efforts to market certain properties and management's assessment as to the likelihood and timing of such potential transactions and the anticipated hold period for such properties.

[2] See Footnote 15 of the Notes to Consolidated Financial Statements for additional disclosure on fair value

[3] During December 2018, the Company recognized an impairment charge of $41.0 million related to a development project, located in Jacksonville FL, for which the Company no longer intends to develop. The Company's intent is to now market the property as-is for sale during 2019. The Company's decision to discontinue this development project was primarily based upon the expectation of increases in estimated costs to complete the project and unfavorable market conditions which would have a negative impact on the Company's return on its investment. In addition, the Company believes its capital allocation to other projects within in its portfolio, which are located within major metro markets, offer a better opportunity for growth and would provide greater value to the Company.

[4] These impairment charges relate to adjustments to property carrying values for properties which the Company has marketed for sale as part of its active capital recycling program and as such has adjusted the anticipated hold periods for such properties.

[5] During 2017, the Company recognized impairment charge of $16.2 million related to a property for which the Company had re-evaluated its long-term plan for the property due to unfavorable local market conditions.