Deferred Revenue and Customer Advances (Tables)

9 Months Ended

Sep. 30, 2018

Deferred Revenue and Customer Advances

Deferred revenue and customer advances consist of the following and are included in short and long-term deferred revenue and customer advances on the balance sheet:

	September 30, 2018		December 31, 2017
	(in thousands)
Maintenance and training	$	59,681	$	57,256
Extended warranty		27,617		24,438
Customer advances, undelivered elements and other		20,042		32,047
Total deferred revenue and customer advances	$	107,340	$	113,741