Fair Value Measurements (Narrative) (Details) $ in Thousands	6 Months Ended
Jun. 30, 2017 USD ($)
Fair Value Measurements [Abstract]
Earnout accretion	$ 488
Deferred purchase payment provision	3,206
Fair value of assets transferred from level 1 to level 2	0
Fair value of liabilities transferred from level 1 to level 2	$ 0

Business Combination, Continegent Consideration, Earnout Accretion

No definition available.

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- Definition

Deferred Purchase Payment Provision

+ References

No definition available.

+ Details

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Namespace Prefix:	ddd_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of transfers of assets measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bb)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

+ Details

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- References

No definition available.

+ Details

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- Definition

Amount of transfers of liabilities measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

+ References

+ Details

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