Selected Income Statement Information (Tables)

12 Months Ended

Dec. 31, 2017

Selected Income Statement Information [Abstract]

Revenue from External Customers by Products and Services [Table Text Block]

The following schedule shows our revenue, costs and gross margins by services and products:

	Year Ended December 31,
(in thousands)	2017			2016			2015
Revenue:
Services	$	1,181,229		$	1,509,786		$	2,001,167
Products	740,278			761,817			1,061,587
Total revenue	1,921,507			2,271,603			3,062,754
Cost of Services and Products:
Services	1,040,817			1,330,218			1,585,305
Products	625,843			615,438			800,316
Unallocated expenses	60,237			46,720			71,704
Total cost of services and products	1,726,897			1,992,376			2,457,325
Gross margin:
Services	140,412			179,568			415,862
Products	114,435			146,379			261,271
Unallocated expenses	(60,237		)	(46,720		)	(71,704		)
Total gross margin	$	194,610		$	279,227		$	605,429