CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY - USD ($) $ in Thousands	Total	Common Stock	Treasury Stock	Additional Paid-In Capital	Accumulated Deficit	Accumulated Other Comprehensive Income (Loss) (AOCI)	Non-controlling Interests
Balance as of at Dec. 31, 2015	$ 357,971	$ 47	$ (55,509)	$ 3,563,848	$ (3,165,321)	$ 40	$ 14,866
Balance as of (in shares) at Dec. 31, 2015		46,763,000	(5,988,000)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Equity-based compensation expense related to stock appreciation rights (SARs) and stock options	108			108
Equity-based compensation related to deferred stock units (DSUs)	193			193
Equity-based compensation related to restricted stock (RS)	7,017			7,017
Issuance of RS, net of forfeitures primarily related to satisfying tax withholdings	(1,536)			(1,536)
Issuance of RS, net of forfeitures primarily related to satisfying tax withholdings (in shares)		(258,000)
Impact of redeemable noncontrolling interests accretion	(1,103)			(1,103)
Impact of subsidiary equity transactions	1,549			1,526		(112)	135
Repurchase of common stock	$ (9,533)		$ (9,533)
Repurchase of common stock (in shares)	(1,010,000)		(1,010,000)
Net income (loss)	$ (28,812)				(27,072)		(1,740)
Balance as of at Jun. 30, 2016	325,854	$ 47	$ (65,042)	3,570,053	(3,192,393)	(72)	13,261
Balance as of (in shares) at Jun. 30, 2016		46,505,000	(6,998,000)
Balance as of at Dec. 31, 2016	365,484	$ 47	$ (129,774)	3,578,204	(3,095,236)	99	12,144
Balance as of (in shares) at Dec. 31, 2016		46,523,000	(11,586,000)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Equity-based compensation expense related to stock appreciation rights (SARs) and stock options	20			20
Equity-based compensation related to deferred stock units (DSUs)	148			148
Equity-based compensation related to restricted stock (RS)	6,142			6,142
Issuance of RS, net of forfeitures primarily related to satisfying tax withholdings	(2,896)			(2,896)
Issuance of RS, net of forfeitures primarily related to satisfying tax withholdings (in shares)		(39,000)
Exercise of SARs and stock options, net of forfeitures related to satisfying tax withholdings	(1)			(1)
Impact of redeemable noncontrolling interests accretion	(69)			(69)
Impact of subsidiary equity transactions	1,264			1,429		(46)	(119)
Repurchase of common stock	$ (25,548)		$ (25,548)
Repurchase of common stock (in shares)	(1,825,531)		(1,826,000)
Net income (loss)	$ (17,514)				(16,533)		(981)
Balance as of at Jun. 30, 2017	$ 327,030	$ 47	$ (155,322)	$ 3,582,977	$ (3,111,769)	$ 53	$ 11,044
Balance as of (in shares) at Jun. 30, 2017		46,484,000	(13,412,000)