Other Intangible, Net and Goodwill (Tables)

6 Months Ended

Jun. 30, 2018

Goodwill and Intangible Assets Disclosure [Abstract]

Schedule of Finite-Lived Intangible Assets [Table Text Block]

	Amortization period (years)	Gross Amount		Accumulated Amortization		Net intangible assets
		(in thousands)
Customer relationships	20	$	13,600	$	1,987	$	11,613
Tradename	0.5-6	8,100		6,404		1,696
Covenants not to compete	1-10	4,200		1,809		2,391
		$	25,900	$	10,200	$	15,700

Goodwill [Line Items]

Schedule of Goodwill [Table Text Block]

	(in thousands)
Balance at December 31, 2017	$	132,410
Acquisition	—
Balance at June 30, 2018	$	132,410