Condensed Consolidated Statements of Changes in Equity - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Deficit [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Treasury Stock [Member]	Total Attributed To Shareholders [Member]	Non-controlling Interests [Member]	Redeemable Non-controlling Interests [Member]
Beginning Balance at Dec. 31, 2014	$ 563,352	$ 96	$ 1,148,908	$ (507,521)	$ (242)	$ (77,699)	$ 563,542	$ (190)	$ 23,071
Beginning Balance (in shares) at Dec. 31, 2014		8,975,833				575,441
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	19,308			19,342			19,342	(34)	417
Net unrealized gain (loss) on securities available-for-sale	4				4		4
Foreign currency translation adjustments	(271)				(271)		(271)
Activity of noncontrolling interests, net									11,489
Cash dividends declared	(4,095)		(4,095)				(4,095)
Repurchases of common shares	$ (14,000)					$ (14,000)	(14,000)
Repurchases of common shares (in shares)	103,818	103,818				103,818
Issuance of common shares related to employee stock transactions	$ 54		54				54
Issuance of common shares related to employee stock transactions (in shares)		39,851
Taxes paid on stock-based compensation	(4,122)		(4,122)				(4,122)
Stock-based compensation	3,784		3,784				3,784
Excess tax benefits from stock-based compensation	1,130		1,130				1,130
Ending Balance at Mar. 31, 2015	565,144	$ 96	1,145,659	(488,179)	(509)	$ (91,699)	565,368	(224)	34,977
Ending Balance (in shares) at Mar. 31, 2015		8,911,866				679,259
Beginning Balance at Dec. 31, 2015	509,457	$ 96	1,140,875	(472,614)	(1,034)	$ (157,699)	509,624	(167)	73,864
Beginning Balance (in shares) at Dec. 31, 2015		8,398,944				1,214,144
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	12,363			12,363			12,363	0	(493)
Net unrealized gain (loss) on securities available-for-sale	160				160		160
Foreign currency translation adjustments	99				99		99
Activity of noncontrolling interests, net									(32,946)
Cash dividends declared	(3,850)		(3,850)				(3,850)
Repurchases of common shares	$ (15,000)					$ (15,000)	(15,000)
Repurchases of common shares (in shares)	176,204	176,204				176,204
Issuance of common shares related to employee stock transactions	$ 375	$ 1	374				375
Issuance of common shares related to employee stock transactions (in shares)		37,091
Taxes paid on stock-based compensation	(1,001)		(1,001)				(1,001)
Stock-based compensation	4,029		4,029				4,029
Tax deficiencies from stock-based compensation	(1,246)		(1,246)				(1,246)
Ending Balance at Mar. 31, 2016	$ 505,386	$ 97	$ 1,139,181	$ (460,251)	$ (775)	$ (172,699)	$ 505,553	$ (167)	$ 40,425
Ending Balance (in shares) at Mar. 31, 2016		8,259,831				1,390,348