Balance Sheet Components - Components (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
RECEIVABLES
Customers	$ 275,250	$ 262,304
Other	5,641	5,508
Total	280,891	267,812
Less allowance for doubtful accounts	8,078	7,812
Total receivables — net	272,813	260,000
INVENTORIES
Raw materials and components parts	154,278	141,671
Work in process	34,832	32,387
Finished goods	63,749	65,066
Total	252,859	239,124
PROPERTY, PLANT AND EQUIPMENT
Land and improvements	33,883	34,343
Buildings and improvements	169,261	157,946
Machinery, equipment and other	328,779	331,146
Office and transportation equipment	98,355	97,250
Construction in progress	10,373	13,377
Total	640,651	634,062
Less accumulated depreciation and amortization	392,835	393,117
Total property, plant and equipment — net	247,816	240,945
ACCRUED EXPENSES
Payroll and related items	67,600	67,209
Management incentive compensation	16,339	12,599
Income taxes payable	8,808	3,836
Insurance	9,416	9,505
Warranty	5,628	7,936
Deferred revenue	12,607	9,885
Restructuring	3,893	6,636
Liability for uncertain tax positions	1,366	3,498
Accrued interest	1,663	1,230
Contingent consideration for acquisition	0	4,705
Other	25,532	26,633
Total accrued expenses	152,852	153,672
OTHER NONCURRENT LIABILITIES
Pension and retiree medical obligations	93,604	76,190
Liability for uncertain tax positions	2,623	4,252
Deferred revenue	2,442	3,763
Other	22,561	18,160
Total other noncurrent liabilities	$ 121,230	$ 102,365