Defined Benefit Plan, Plan Assets at Fair Value, Period of Recognition of Changes

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- Definition

Percentage Of Ownership Interests

+ References

No definition available.

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 720
-SubTopic 35
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6420018&loc=d3e36677-107848

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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.

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

No definition available.

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Summary of significant accounting policies - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Property, Plant and Equipment [Line Items]
Advertising costs incurred	$ 1.6	$ 2.7	$ 4.9
Maximum estimated revenue-producing lives of computer software products from the date of release	3 years
Period of recognition in changes in fair value of plan assets	4 years
Intelligent Processing Solutions Ltd.
Property, Plant and Equipment [Line Items]
Percentage of ownership interest	51.00%
Buildings \| Minimum
Property, Plant and Equipment [Line Items]
Estimated useful lives	20 years
Buildings \| Maximum
Property, Plant and Equipment [Line Items]
Estimated useful lives	50 years
Machinery and office equipment \| Minimum
Property, Plant and Equipment [Line Items]
Estimated useful lives	4 years
Machinery and office equipment \| Maximum
Property, Plant and Equipment [Line Items]
Estimated useful lives	7 years
Rental equipment
Property, Plant and Equipment [Line Items]
Estimated useful lives	4 years
Internal-use software \| Minimum
Property, Plant and Equipment [Line Items]
Estimated useful lives	3 years
Internal-use software \| Maximum
Property, Plant and Equipment [Line Items]
Estimated useful lives	10 years