Condensed Consolidated Statements of Changes in Equity (Unaudited) - USD ($) $ in Thousands	Total	Series D convertible preferred stock	Common Stock	Preferred Stock Series D convertible preferred stock	Additional Paid-in Capital	Accumulated Deficit	Accumulated Other Comprehensive Income (Loss)	Treasury Stock	Total Attributed To Stockholders	Total Attributed To Stockholders Series D convertible preferred stock	Non- controlling Interests
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative effect adjustment for adoption of ASU	$ 1,052					$ 1,052			$ 1,052
Beginning Balance (in shares) at Dec. 31, 2016			5,889,013	0				3,230,045
Beginning Balance at Dec. 31, 2016	321,673		$ 91	$ 0	$ 1,090,331	(424,279)	$ (224)	$ (344,246)	321,673		$ 0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	13,027					13,027			13,027
Net unrealized gain (loss) on securities available-for-sale	88						88		88
Foreign currency translation adjustments	0
Issuance of stock, net of offering costs (in shares)			1,046,500	1,150,000
Issuance of stock, net of offering costs	109,320	$ 110,837	$ 10	$ 110,837	109,310				109,320	$ 110,837
Cash dividends declared, preferred	(2,084)				(2,084)				(2,084)
Cash dividends declared, common	(3,322)				(3,322)				(3,322)
Issuance of common shares related to employee stock transactions (in shares)			53,631
Issuance of common shares related to employee stock transactions	86		$ 1		85				86
Taxes paid on stock-based compensation	(2,464)				(2,464)				(2,464)
Stock-based compensation	4,175				4,175				4,175
Ending Balance (in shares) at Mar. 31, 2017			6,989,144	1,150,000				3,230,045
Ending Balance at Mar. 31, 2017	552,388		$ 102	$ 110,837	1,196,031	(410,200)	(136)	$ (344,246)	552,388		0
Beginning Balance at Dec. 31, 2016	37,266
Increase (Decrease) in Redeemable Non-controlling Interests [Roll Forward]
Net income (loss)	718
Activity of noncontrolling interests, net	6,992
Ending Balance at Mar. 31, 2017	44,976
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative effect adjustment for adoption of ASU						(178)	178
Beginning Balance (in shares) at Dec. 31, 2017			7,159,645	1,150,000				3,296,289
Beginning Balance at Dec. 31, 2017	605,224		$ 105	$ 110,843	1,216,173	(386,216)	(600)	$ (351,748)	588,557		16,667
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	23,972					23,300			23,300		672
Net unrealized gain (loss) on securities available-for-sale	(249)						(249)		(249)
Foreign currency translation adjustments	10						10		10
Activity of noncontrolling interests, net	(720)										(720)
Cash dividends declared, preferred	(2,084)				(2,084)				(2,084)
Cash dividends declared, common	(3,394)				(3,394)				(3,394)
Issuance of common shares related to employee stock transactions (in shares)			57,798
Issuance of common shares related to employee stock transactions	698				698				698
Taxes paid on stock-based compensation	(5,014)				(5,014)				(5,014)
Stock-based compensation	6,963				6,963				6,963
Ending Balance (in shares) at Mar. 31, 2018			7,217,443	1,150,000				3,296,289
Ending Balance at Mar. 31, 2018	625,406		$ 105	$ 110,843	$ 1,213,342	$ (363,094)	$ (661)	$ (351,748)	$ 608,787		$ 16,619
Beginning Balance at Dec. 31, 2017	4,178
Increase (Decrease) in Redeemable Non-controlling Interests [Roll Forward]
Net income (loss)	(145)
Activity of noncontrolling interests, net	129
Ending Balance at Mar. 31, 2018	$ 4,162