Significant Accounting Policies (Details Textual) $ in Millions	12 Months Ended
	Dec. 31, 2016 USD ($) Entity	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Accounting Policies [Abstract]
Wholly-owned bankruptcy remote special-purpose corporations | Entity	1
Interest expense net of interest income on bank deposits | $	$ 1.9	$ 1.1	$ 0.9