Investment Income (Details) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Investment Income [Abstract]
Interest and dividend income	$ 120,000	$ 213,000	$ 1,886,000	$ 2,836,000
Investment gain	111,000	9,780,000	1,407,000	9,780,000
Equity earnings (loss)	0	(2,000)	0	(522,000)
Total investment income	231,000	9,991,000	3,293,000	12,094,000
Gain associated in connection with previously written-off investment			$ 1,400,000	$ 9,800,000