Goodwill and Intangible Assets - Assumptions for Our Annual Impairment Assessments of Goodwill (Details)	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Disclosure of information for cash-generating units [line items]
Annual revenue growth rate	2.00%
Capital equipment CGU
Disclosure of information for cash-generating units [line items]
Annual revenue growth rate	4.00%	9.00%	7.00%
Term used to extrapolate cash flow projections	5 years	6 years	7 years
Discount rate	13.00%	17.00%	17.00%
A & D CGU
Disclosure of information for cash-generating units [line items]
Term used to extrapolate cash flow projections	5 years	4 years
Discount rate	11.00%	9.00%
Atrenne CGU
Disclosure of information for cash-generating units [line items]
Annual revenue growth rate	12.00%
Term used to extrapolate cash flow projections	4 years
Discount rate	13.00%

Growth Rate Used To Extrapolate Cash Flow Projections, Term

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- Definition

The discount rate applied to cash flow projections for a cash-generating unit (group of units). [Refer: Cash-generating units [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Number 36
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 36
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-Subparagraph e
-Clause v
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-URIDate 2017-03-09

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- Definition

The growth rate used to extrapolate cash flow projections beyond the period covered by the most recent budgets/forecasts for a cash-generating unit (group of units). [Refer: Cash-generating units [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 36
-IssueDate 2017-01-01
-Paragraph 134
-Subparagraph d
-Clause iv
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=36&date=2017-03-01&anchor=para_134_d_iv&doctype=Standard
-URIDate 2017-03-09

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 36
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-Paragraph 134
-Subparagraph e
-Clause iv
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=36&date=2017-03-01&anchor=para_134_e_iv&doctype=Standard
-URIDate 2017-03-09

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- Definition

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

+ References

No definition available.

+ Details

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