CONSOLIDATED STATEMENTS OF EQUITY - USD ($) shares in Thousands, $ in Thousands	Total	Common stock	Additional paid-in capital	Retained earnings	Accumulated other comprehensive income (loss)	Treasury stock, at cost	Non-controlling interests
Balance at Dec. 31, 2016	$ 62,194	$ 25,413	$ 107,288	$ 333,786	$ (1,745)	$ (403,953)	$ 1,405
Balance (in shares) at Dec. 31, 2016		25,413
Increase (Decrease) in Equity
Net (loss) income	311,631			308,891			2,740
Other comprehensive income, net of tax	2,478				2,478
Distributions to non-controlling interest holders	(2,772)						(2,772)
Share-based compensation expense	4,255		4,255
Exercise of stock options and issuance of restricted shares	2,374			(13,491)		15,865
Treasury shares withheld for the payment of tax on restricted share unit and restricted share issuances and stock option exercises	(1,164)			(1,654)		490
Repurchase of shares	(39,011)					(39,011)
Balance at Dec. 31, 2017	339,985	$ 25,413	112,475	626,600	733	(426,609)	1,373
Balance (in shares) at Dec. 31, 2017		25,413
Increase (Decrease) in Equity
Net (loss) income	(2,699)			(5,382)			2,683
Distributions to non-controlling interest holders	(2,819)						(2,819)
Share-based compensation expense	10,192		10,192
Exercise of stock options and issuance of restricted shares	3,644			(19,245)		22,889
Treasury shares withheld for the payment of tax on restricted share unit and restricted share issuances and stock option exercises	(825)			(1,603)		778
Repurchase of shares	(40,362)					(40,362)
Balance at Dec. 31, 2018	296,668	$ 25,413	122,667	590,655	0	(443,304)	1,237
Balance (in shares) at Dec. 31, 2018		25,413
Increase (Decrease) in Equity
Net (loss) income	(305,857)			(307,969)			2,112
Distributions to non-controlling interest holders	(2,752)						(2,752)
Share-based compensation expense	11,874		11,002				872
Exercise of stock options and issuance of restricted shares	400			(7,222)		7,622
Treasury shares withheld for the payment of tax on restricted share unit and restricted share issuances and stock option exercises	(1,695)			(3,438)		1,743
Repurchase of shares	(19,995)					(19,995)
Balance at Dec. 31, 2019	$ (21,357)	$ 25,413	$ 133,669	$ 272,026	$ 0	$ (453,934)	$ 1,469
Balance (in shares) at Dec. 31, 2019		25,413