Summary of Significant Accounting Policies - Additional Information (Details)	12 Months Ended
	Dec. 31, 2018 USD ($) segment plan	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Sep. 30, 2018 USD ($)	Jan. 01, 2018 USD ($)
Summary Of Significant Accounting Policies [Line Items]
Number of reportable segments | segment	3
Standard product warranty period	1 year
Deposits with foreign banks	$ 77,500,000	$ 98,800,000
Sales demonstration inventory turnover period (up to)	3 years
Refurbished sales demonstration inventory turnover period	12 months
Service inventory turnover period	12 months
Service inventory not for sale, useful life	3 years
Reserve percentage of FIFO obsolete and excess inventory	100.00%
Depreciation expense	$ 12,900,000	12,300,000	$ 10,900,000
Indefinite-lived intangible assets	$ 0	0
Intangible assets weighted-average amortization period	8 years
Number of compensation plans | plan	2
Revenue recognized	$ 25,000,000.0
Retained earnings	175,353,000	168,624,000
Capitalized contract cost, net	$ 2,700,000
Revenue, remaining performance obligation				$ 100,000
Performance Shares
Summary Of Significant Accounting Policies [Line Items]
Vesting period, years	3 years
Long Lived Assets
Summary Of Significant Accounting Policies [Line Items]
Assets impairment charges	$ 0	$ 0	$ 0
Minimum
Summary Of Significant Accounting Policies [Line Items]
Account receivable period due	30 days
Other intangible assets, useful life	3 years
Minimum | Product technology and patents
Summary Of Significant Accounting Policies [Line Items]
Other intangible assets, useful life	7 years
Maximum
Summary Of Significant Accounting Policies [Line Items]
Account receivable period due	90 days
Other intangible assets, useful life	20 years
Maximum | Product technology and patents
Summary Of Significant Accounting Policies [Line Items]
Other intangible assets, useful life	20 years
Accounting Standards Update 2016-02 | Minimum
Summary Of Significant Accounting Policies [Line Items]
Right-of-use asset	$ 14,000,000
Lease liability	14,000,000
Accounting Standards Update 2016-02 | Maximum
Summary Of Significant Accounting Policies [Line Items]
Right-of-use asset	17,000,000
Lease liability	17,000,000
Prepaid Expenses and Other Current Assets
Summary Of Significant Accounting Policies [Line Items]
Capitalized contract cost, net	1,800,000
Other Noncurrent Assets
Summary Of Significant Accounting Policies [Line Items]
Capitalized contract cost, net	$ 900,000
Difference between Revenue Guidance in Effect before and after Topic 606 [Member] | Accounting Standards Update 2014-09
Summary Of Significant Accounting Policies [Line Items]
Retained earnings					$ 1,800,000
Capitalized contract cost, net					$ 2,400,000