Interest and Other Income - Interest Income, Net (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Income Statement [Abstract]
Interest income	$ 1,332	$ 1,217	$ 4,231	$ 3,341
Interest expense	(778)	(745)	(2,468)	(1,000)
Interest income, net	$ 554	$ 472	$ 1,763	$ 2,341