CONSOLIDATED STATEMENT OF CHANGES IN STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Common Stock	Retained Earnings	Accumulated Other Comprehensive (Loss) Income	Treasury Stock	Non-controlling Interest
Beginning Balance (in shares) at Dec. 31, 2014		92,302,636
Beginning Balance at Dec. 31, 2014	$ 979,701	$ 892,237	$ 80,582	$ (1,325)	$ (285)	$ 8,492
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Capital contributions from non-controlling interest	(68)					(68)
Issuance of common stock for director fees (in shares)		9,660
Issuance of common stock for director fees	150	$ 150
Repurchase of common shares (in shares)		(16,982,739)
Repurchase of common shares	(305,004)				(305,004)
Other comprehensive income (loss)	639			639
Net income (loss)	(1,971)		(1,731)			(240)
Ending Balance (in shares) at Dec. 31, 2015		75,329,557
Ending Balance at Dec. 31, 2015	673,447	$ 892,387	78,851	(686)	(305,289)	8,184
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Capital contributions from non-controlling interest	10,353					10,353
Capital distribution to non-controlling interest	(600)					(600)
Issuance of common stock for director fees (in shares)		8,919
Issuance of common stock for director fees	131	$ 131
Reduction in excess tax benefits on stock options	(369)	$ (369)
Repurchase of common shares (in shares)		(995,650)
Repurchase of common shares	(14,820)				(14,820)
Retirement of treasury stock		$ (320,109)			320,109
Other comprehensive income (loss)	3,193			3,193
Net income (loss)	15,464		15,895			(431)
Ending Balance (in shares) at Dec. 31, 2016		74,342,826
Ending Balance at Dec. 31, 2016	686,799	$ 572,040	94,746	2,507	0	17,506
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Capital contributions from non-controlling interest	193					193
Capital distribution to non-controlling interest	(2,330)					(2,330)
Issuance of common stock for director fees (in shares)		5,334
Issuance of common stock for director fees	76	$ 76
Repurchase of common shares (in shares)		(8,450,294)
Repurchase of common shares	(147,422)				(147,422)
Retirement of treasury stock		$ (147,422)			147,422
Other comprehensive income (loss)	(3,968)			(3,968)
Net income (loss)	59,236		59,578			(342)
Ending Balance (in shares) at Dec. 31, 2017		65,897,866
Ending Balance at Dec. 31, 2017	$ 592,584	$ 424,694	$ 154,324	$ (1,461)	$ 0	$ 15,027