Employee Benefit Plans (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Components of net periodic pension expense:
Interest cost	$ 571	$ 571	$ 1,142	$ 1,143
Expected return on plan assets	(697)	(800)	(1,394)	(1,599)
Amortization of net loss	384	357	768	714
Total net periodic pension expense	$ 258	$ 128	$ 516	$ 258