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- Definition

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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- Definition

Amount charged to advertising expense for the period, which are expenses incurred with the objective of increasing revenue for a specified brand, product or product line.

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-Publisher FASB
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-Subparagraph (b)
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- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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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.

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- Definition

Amount of cash restricted as to withdrawal or usage. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Significant Accounting Policies (Narrative) (Details)	12 Months Ended
Significant Accounting Policies (Narrative) (Details)	Dec. 31, 2018 USD ($) segment	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Accounting Policies [Line Items]
Number of principal reporting segments \| segment	3
Restricted cash	$ 0	$ 0
Accumulated depreciation relating to rental equipment	$ 131,905,000	125,629,000
Options
Accounting Policies [Line Items]
Award vesting period (years)	5 years
Minimum
Accounting Policies [Line Items]
Estimated useful lives	3 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	$ 11,145,000	9,413,000
Selling, General and Administrative expenses
Accounting Policies [Line Items]
Advertising expense	11,773,000	9,566,000	$ 7,742,000
Product development and engineering costs	$ 10,429,000	$ 9,849,000	$ 8,847,000