Condensed Consolidated Statements of Operations and Comprehensive Income (Loss) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Condensed Consolidated Statements of Operations and Comprehensive Income (Loss) [Abstract]
General and administrative expenses	$ (1,336)	$ (3,361)	$ (2,676)	$ (7,107)
Operating income (loss)	(1,336)	(3,361)	(2,676)	(7,107)
Interest and investment income	110	343	401	632
Interest expense	(4)	(5)	(7)	(8)
Other income (expense)	(651)	(341)	(1,576)	(371)
Income (loss) from continuing operations before income taxes and equity in net income (loss) of affiliates	(1,881)	(3,364)	(3,858)	(6,854)
Income tax (provision) benefit	(9,480)	(2,170)	(20,152)	(4,985)
Income (loss) from continuing operations before equity in net income (loss) of affiliates	(11,361)	(5,534)	(24,010)	(11,839)
Equity in net income (loss) of affiliates	64,363	132	62,194	(7,149)
Income (loss) from continuing operations	53,002	(5,402)	38,184	(18,988)
Income (loss) from discontinued operations, net of tax provision	(1)	(2,488)	(8)	(2,365)
Net income (loss)	53,001	(7,890)	38,176	(21,353)
Other comprehensive income (loss), net of tax	286	491	1,049	1,863
Comprehensive income (loss)	$ 53,287	$ (7,399)	$ 39,225	$ (19,490)
Basic
Income (loss) from continuing operations	$ 1.71	$ (0.18)	$ 1.23	$ (0.62)
Income (loss) from discontinued operations, net of tax		$ (0.08)		$ (0.08)
Net income (loss)	$ 1.71	$ (0.26)	$ 1.23	$ (0.70)
Diluted
Income (loss) from continuing operations	$ 1.67	$ (0.18)	$ 1.19	$ (0.62)
Income (loss) from discontinued operations, net of tax		$ (0.08)		$ (0.08)
Net income (loss)	$ 1.67	$ (0.26)	$ 1.19	$ (0.70)
Weighted average common shares outstanding:
Basic	30,920	30,793	30,920	30,781
Diluted	31,004	30,793	31,004	30,781