Unaudited Consolidated Statements of Comprehensive Income (Loss) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Unaudited Consolidated Statements of Comprehensive Income (Loss) [Abstract]
Net income (loss)	$ 4,050	$ (5,504)	$ 15,556	$ (20,702)
Unrealized net gains (losses) on securities:
Unrealized holding net gains (losses) arising during the period	(4,635)	1,030	3,003	4,956
Less: reclassification adjustment for net gains (losses) included in net income (loss)	(370)	1,089	(397)	1,134
Unrealized net gains (losses) on securities	(4,265)	(59)	3,400	3,822
Foreign currency translation adjustments	(223)	61	(19)	288
Other comprehensive income (loss)	(4,488)	2	3,381	4,110
Comprehensive income (loss)	$ (438)	$ (5,502)	$ 18,937	$ (16,592)