Investments (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Fair Value Disclosures [Abstract]
Investments carried at fair value	$ 3,058		$ 2,907
Dividend and interest income from investments	32
Net unrealized gains recognized	$ 120	$ 16