Income Taxes, Provision for Income Taxes (Details) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Current [Abstract]
Federal		$ 379	$ 263	$ 0
State		(7)	(4,295)	2
Total current		372	(4,032)	2
Deferred [Abstract]
Federal		0	(8,948)	(5,082)
State		0	(2,427)	(834)
Total deferred		0	(11,375)	(5,916)
Income tax expense (benefit)		372	(15,407)	(5,914)
Tax benefit related to unrealized gains on investments in available-for-sale securities recorded in continuing operations			(12,800)	(5,900)
Tax expense related to unrealized gains on investments in available-for-sale securities recorded in other comprehensive income			$ 12,800	$ 5,900
State Jurisdiction [Member] | California Franchise Tax Board [Member] | Tax Year 2009 [Member]
Income Taxes [Abstract]
Franchise tax refund		$ 4,300
Research Tax Credit Carryforward [Member] | California Franchise Tax Board [Member] | Tax Year 2009 [Member]
Income Taxes [Abstract]
Increase in research credit carry over	$ 4,300