Other Income (Expenses) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Other Income and Expenses [Abstract]
Interest and investment income	$ 155	$ 148	$ 336
Income tax expense	(460)	(645)	(1,016)
Acquisition related expenses	0	0	(152)
Other non-operating income	746	10	203
Total other income (expense)	$ 441	$ (487)	$ (629)