Interim Condensed Consolidated Statements of Comprehensive Income (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Net Income	$ 13,614	$ 13,611	$ 26,290	$ 32,335
Other Comprehensive Income (Loss):
Unrealized gains (losses) on investments in marketable securities	5,051	(5,107)	13,020	537
Income tax (expense) benefit related to items of other comprehensive income	(1,949)	2,018	(5,059)	(187)
Other comprehensive income (loss), net of tax	3,102	(3,089)	7,961	350
Comprehensive Income	$ 16,716	$ 10,522	$ 34,251	$ 32,685