Condensed Consolidated Statements of Equity (Unaudited) (USD $) In Thousands, unless otherwise specified	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Parent [Member]	Noncontrolling Interest [Member]	Total
Balance at Dec. 31, 2012	$ 46	$ 732,140	$ (44,326)	$ 651	$ 688,511	$ 7,096	$ 695,607
Balance (in Shares) at Dec. 31, 2012	45,431
Stock-based compensation		1,543			1,543		1,543
Cash paid to noncontrolling interest						(189)	(189)
Increase in noncontrolling interest in ORTP LLC						4,906	4,906
Net income (loss)			(5,034)		(5,034)	85	(4,949)
Other comprehensive income (loss), net of related taxes:
Amortization of unrealized gains in respect of derivative instruments designated for cash flow hedge (net of related tax)				(42)	(42)		(42)
Balance at Mar. 31, 2013	46	733,683	(49,360)	609	684,978	11,898	696,876
Balance (in Shares) at Mar. 31, 2013	45,431
Balance at Dec. 31, 2013	46	735,295	(3,088)	487	732,740	12,371	745,111
Balance (in Shares) at Dec. 31, 2013	45,461
Stock-based compensation		1,440			1,440		1,440
Exercise of options by employees and directors (in Shares)	18
Cash paid to noncontrolling interest						(140)	(140)
Increase in noncontrolling interest in ORTP LLC						257	257
Cash dividend paid, $0.06 per share			(2,727)		(2,727)		(2,727)
Net income (loss)			21,552		21,552	237	21,789
Other comprehensive income (loss), net of related taxes:
Amortization of unrealized gains in respect of derivative instruments designated for cash flow hedge (net of related tax)				(36)	(36)		(36)
Balance at Mar. 31, 2014	$ 46	$ 736,735	$ 15,737	$ 451	$ 752,969	$ 12,725	$ 765,694
Balance (in Shares) at Mar. 31, 2014	45,479