CONSOLIDATED STATEMENTS OF EQUITY (Unaudited) - USD ($) $ in Thousands	Total	Shares of Beneficial Interest, $1.00 Par	Capital Contributed in Excess of Par	Accumulated Other Comprehensive Loss	Distributions in Excess of Net Income	Non- controlling interest	Series B Preferred Stock Preferred Shares $.01 par	Series C Preferred Stock Preferred Shares $.01 par	Series D Preferred Stock Preferred Shares $.01 par
Beginning balance at Dec. 31, 2020	$ 126,940	$ 5,302	$ 1,846,012	$ (20,620)	$ (1,699,638)	$ (4,270)	$ 35	$ 69	$ 50
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(43,980)				(42,746)	(1,234)
Other comprehensive income (loss)	2,604			2,540		64
Shares issued under employee compensation plans, net of shares retired	(647)	(18)	(629)
Amortization of deferred compensation	1,321		1,321
Ending balance at Mar. 31, 2021	86,238	5,284	1,846,704	(18,080)	(1,742,384)	(5,440)	35	69	50
Beginning balance at Dec. 31, 2020	126,940	5,302	1,846,012	(20,620)	(1,699,638)	(4,270)	35	69	50
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(69,360)
Ending balance at Jun. 30, 2021	64,715	5,284	1,847,853	(15,475)	(1,766,981)	(6,120)	35	69	50
Beginning balance at Mar. 31, 2021	86,238	5,284	1,846,704	(18,080)	(1,742,384)	(5,440)	35	69	50
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(25,380)				(24,597)	(783)
Other comprehensive income (loss)	2,670			2,605		65
Amortization of deferred compensation	1,149		1,149
Other changes in noncontrolling interest, net	38					38
Ending balance at Jun. 30, 2021	64,715	5,284	1,847,853	(15,475)	(1,766,981)	(6,120)	35	69	50
Beginning balance at Dec. 31, 2021	7,047	5,347	1,851,866	(8,830)	(1,832,375)	(9,115)	35	69	50
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(32,973)				(32,469)	(504)
Other comprehensive income (loss)	5,807			5,734		73
Shares issued under employee compensation plans, net of shares retired	4,449	28	4,421
Amortization of deferred compensation	814		814
Ending balance at Mar. 31, 2022	(14,856)	5,375	1,857,101	(3,096)	(1,864,844)	(9,546)	35	69	50
Beginning balance at Dec. 31, 2021	7,047	5,347	1,851,866	(8,830)	(1,832,375)	(9,115)	35	69	50
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(43,988)
Ending balance at Jun. 30, 2022	(21,865)	5,369	1,857,496	475	(1,875,634)	(9,725)	35	69	50
Beginning balance at Mar. 31, 2022	(14,856)	5,375	1,857,101	(3,096)	(1,864,844)	(9,546)	35	69	50
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(11,015)				(10,790)	(225)
Other comprehensive income (loss)	3,617			3,571		46
Shares issued under employee compensation plans, net of shares retired	(175)	(6)	(169)
Amortization of deferred compensation	564		564
Ending balance at Jun. 30, 2022	$ (21,865)	$ 5,369	$ 1,857,496	$ 475	$ (1,875,634)	$ (9,725)	$ 35	$ 69	$ 50