Financial Instruments (Details Textual) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Financial Instruments (Textual) [Abstract]
Short-term investments contractual maturity period minimum									5 months
Short-term investments contractual maturity period maximum									12 months
Average short-term investments maturity period									4 months
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Goodwill impairment charges	$ 5,698	$ 0	$ 0	$ 0	$ 0	$ 0	$ 0	$ 0	$ 5,698	$ 0	$ 0
Discontinued Operations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Goodwill impairment charges			$ 5,700				$ 3,400