Summary of Significant Accounting Policies (Other Income) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Accounting Policies [Abstract]
Gain (loss) on warrants	$ 1,165	$ (1,193)	$ 700
Interest income	5,421	2,256	1,035
Accretion of interest income from debt discount on notes receivable	772	129	0
Gain on long-term investment	189	135	0
Other income	3	(148)	1
Other, net	$ 7,550	$ 1,179	$ 1,736