Retirement Plans (Tables)

6 Months Ended

Jun. 30, 2016

Compensation and Retirement Disclosure [Abstract]

Summary of Net Periodic Pension Expense for ACS Retirement Plan

The following table presents the net periodic pension expense for the ACS Retirement Plan for the three and six-month periods ended June 30, 2016 and 2015:

	Three Months Ended						Six Months Ended
	June 30,						June 30,
	2016			2015			2016			2015
Interest cost	$	168		$	165		$	335		$	331
Expected return on plan assets		(181	)		(186	)		(362	)		(373	)
Amortization of loss		230			294			461			588
Net periodic pension expense	$	217		$	273		$	434		$	546