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Significant Accounting Policies - Additional Information (Details) $ in Millions | 12 Months Ended
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Dec. 31, 2020 USD ($) Segment | Dec. 31, 2019 USD ($) | Dec. 31, 2018 USD ($)
Significant Accounting Policies [Line Items] |  |  |
Number of reportable segments | Segment | 2 |  |
Foreign currency transaction (gain) loss | $ (0.4) | $ (0.1) | $ 0.4
Depreciation expense | 35.2 | 32.7 | 28.4
Goodwill impairment | 0.0 | 0.0 | 0.0
Indefinite-lived intangible asset impairment | 0.0 | 0.0 | 0.0
Deferred revenue | $ 4.2 | $ 3.3 |
Minimum |  |  |
Significant Accounting Policies [Line Items] |  |  |
Percentage of reporting unit fair value in excess of carrying amount | 50.00% | 20.00% |
Maximum |  |  |
Significant Accounting Policies [Line Items] |  |  |
Rental equipment operating lease term | 5 years |  |
Building | Minimum |  |  |
Significant Accounting Policies [Line Items] |  |  |
Useful life | 8 years |  |
Building | Maximum |  |  |
Significant Accounting Policies [Line Items] |  |  |
Useful life | 40 years |  |
Machinery and Equipment | Minimum |  |  |
Significant Accounting Policies [Line Items] |  |  |
Useful life | 3 years |  |
Machinery and Equipment | Maximum |  |  |
Significant Accounting Policies [Line Items] |  |  |
Useful life | 15 years |  |
Leasehold Improvements |  |  |
Significant Accounting Policies [Line Items] |  |  |
Useful life description | over the shorter of the remaining life of the lease or the useful life of the improvement |  |
Selling, engineering, general and administrative expenses |  |  |
Significant Accounting Policies [Line Items] |  |  |
Research and development expenses | $ 12.2 | $ 13.6 | $ 13.0

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- Definition Amount of deferred income and obligation to transfer product and service to customer for which consideration has been received or is receivable. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(5)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
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- Definition The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 985 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6501960&loc=d3e128462-111756 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 730 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6420194&loc=d3e21568-108373 + Details
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