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Significant Accounting Policies (Narrative) (Details) $ in Thousands | 12 Months Ended
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Dec. 31, 2016 USD ($) segment | Dec. 31, 2015 USD ($) | Dec. 31, 2014 USD ($)
Accounting Policies [Line Items] |  |  |
Number of principal reporting segments | segment | 3 |  |
Period of delayed payment terms | 11 months |  |
Accumulated depreciation relating to rental equipment | $ 113,412 | $ 107,094 |
Options |  |  |
Accounting Policies [Line Items] |  |  |
Award vesting period (years) | 5 years |  |
Minimum |  |  |
Accounting Policies [Line Items] |  |  |
Estimated useful lives | 12 years |  |
Maximum |  |  |
Accounting Policies [Line Items] |  |  |
Estimated useful lives | 25 years |  |
Option term (years) | 10 years |  |
Rental Equipment |  |  |
Accounting Policies [Line Items] |  |  |
Accumulated depreciation relating to rental equipment | $ 10,430 | 8,322 |
Selling, General and Administrative expenses |  |  |
Accounting Policies [Line Items] |  |  |
Advertising expense | 7,742 | 7,670 | $ 7,368
Product development and engineering costs | 8,847 | $ 8,590 | $ 8,427
Pension Plans, Defined Benefit |  |  |
Accounting Policies [Line Items] |  |  |
Amount expenses of accumulated pension actuarial losses | 2,889 |  |
Pension Plans, Defined Benefit | Hourly Employees’ Pension Plan |  |  |
Accounting Policies [Line Items] |  |  |
Amount of final contribution | 622 |  |
Amount expenses of accumulated pension actuarial losses | 2,889 |  |
Foreign Currency Forward |  |  |
Accounting Policies [Line Items] |  |  |
Outstanding forward exchange contracts related to sales | $ 1,384 |  |

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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://www.xbrl.org/2003/role/presentationRef -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 Reference 2: http://www.xbrl.org/2003/role/presentationRef -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 + Details
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