Other Employee Benefit Plans (Details 2) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Pension and Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), before Tax [Abstract]
Net earnings (loss)	$ 78	$ 500	$ (372)
Prior service cost	24	161	160
Pension and Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), before Tax	102	661	$ (212)
Pension and Other Postretirement Benefit Plans, Amounts that Will be Amortized from Accumulated Other Comprehensive Income (Loss) in Next Fiscal Year [Abstract]
Net loss	(1,630)	(1,708)
Prior service cost	15	(9)
Total recognized in AOCI	$ (1,615)	$ (1,717)