Fair Value Measurements (Tables)

6 Months Ended

Jun. 30, 2018

Fair Value Disclosures [Abstract]

Fair Value, Assets Measured on Recurring Basis [Table Text Block]

			Fair Value Measurements at June 30, 2018
	Total			Using Fair Value Hierarchy
Assets	Fair Value			Level 1		Level 2		Level 3
Company-owned life insurance	$	1,591		$	—	$	1,591	$	—
Total	$	1,591		$	—	$	1,591	$	—

			Fair Value Measurements at December 31, 2017
	Total			Using Fair Value Hierarchy
Assets	Fair Value			Level 1		Level 2		Level 3
Company-owned life insurance	$	1,594		$	—	$	1,594	$	—
Total	$	1,594		$	—	$	1,594	$	—