Inventory Inventory (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2017	Dec. 31, 2016
Inventory [Line Items]
Components and subassemblies		$ 28,494	$ 31,695
Work in process		44,651	39,894
Finished goods		40,470	16,665
Total		113,615	88,254
Inventory written off	$ 600
Located at Customer Sites [Member]
Inventory [Line Items]
Finished goods		32,100	10,500
Finished Goods Inventory [Member]
Inventory [Line Items]
Finished goods		$ 34,700	$ 11,900