Acquisitions and Divestitures - Divestitures (Details) - USD ($) $ in Thousands		12 Months Ended
Dec. 22, 2015	Dec. 31, 2015
Divestitures
Pre-tax gain on sale		$ 107,699
Energy research business \| Sale of subsidiaries
Divestitures
Number of years as exclusive sales partner	2 years
After-tax gain on sale of business	$ 91,400
Currency translation losses	200
Cash proceeds from sale	120,500
Working capital adjustment	(1,615)
Carrying value of net assets disposed	(3,025)
Direct selling costs	(8,161)
Pre-tax gain on sale	$ 107,699

Amount of assets disposed in disposal including discontinued operation.

No definition available.

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- Definition

Amount of direct selling costs paid or payable for the disposal of assets and liabilities, including discontinued operation.

+ References

No definition available.

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Amount of working capital adjustment in disposal including discontinued operation.

+ References

No definition available.

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- Definition

Represents information pertaining to the number of years serving as exclusive sales partner.

+ References

No definition available.

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- Definition

Amount of gain (loss), after tax expense or benefit and not previously recognized, resulting from the sale of a business component.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1361-107760

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6892542&loc=d3e957-107759

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- Definition

Amount of foreign currency translation gains or losses included in the disposal group, whether or not a component of the entity (discontinued operation), that were previously reported in accumulated other comprehensive Income or Loss.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 830
-SubTopic 30
-Section 45
-Paragraph 20
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=6915805&loc=d3e32211-110900

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- Definition

Gain (loss) from sale or disposal of an organization or integrated set of activities (for example, but not limited to, a partnership or corporation) engaged in providing a product or service in a commercial, industrial, or professional environment.

+ 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

The cash inflow associated with the amount received from the sale of a portion of the company's business, for example a segment, division, branch or other business, during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3179-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
-URI http://asc.fasb.org/extlink&oid=6516133

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