Other Comprehensive Income (Loss) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Other comprehensive income (loss), before tax amount
Foreign currency translation, before tax amount	$ 1,155	$ 4,106	$ (9,139)
Unrealized holding gains (losses) on available-for-sale securities, before tax amount	123,233	265,785	(13,965)
Recognition of previously unrealized (gains) losses on available-for-sale securities included in net income (loss), before tax amount	(148,603)	(150,239)	11,790
Other comprehensive income (loss), before tax amount	(24,215)	119,652	(11,314)
Other comprehensive income loss tax (expense) benefit
Unrealized holding gains (losses) on available-for-sale securities, tax (expense) benefit	9,284	(12,892)
Other Comprehensive Income (Loss), tax (expense) benefit	9,284	(12,892)
Other comprehensive income (loss):
Foreign currency translation adjustments, net of tax amount	1,155	4,106	(9,139)
Unrealized holding gains (losses) on available-for-sale securities, net of tax amount	132,517	252,893	(13,965)
Recognition of previously unrealized (gains) losses on available-for-sale securities included in net income (loss), net of tax amount	(148,603)	(150,239)	11,790
Total other comprehensive income (loss), net of tax	$ (14,931)	$ 106,760	$ (11,314)