Supplemental Financial Information (Tables)

3 Months Ended

Mar. 31, 2019

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Schedule of noncash investing and financing activities

	For the three months ended March 31,
	2019			2018
	(in thousands)
Employee benefits paid in Class A common stock	$	6,654		$	7,605
Increase (decrease) in capital expenditures included in accounts payable, net	$	(15,320	)	$	585

Schedule of cost of sales and research and development costs

The table below summarizes the research and development costs incurred in connection with customers’ orders included in cost of sales and other expenses we incurred for research and development.

		For the three months ended March 31,
		2019		2018
	(in thousands)
Cost of sales		$	5,395	$	6,598
Research and development		$	6,888	$	7,137