Defined Benefit Plans (Details Textual) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Defined Benefit Plan (Textual) [Abstract]
Employer contributions	$ 0.1	$ 0.2	$ 0.3	$ 0.3
Additional employer contributions, expected to be paid during the remainder of fiscal year			$ 0.3