XML 92 R60.htm IDEA: XBRL DOCUMENT
v2.4.0.8

Goodwill - Additional Information (Detail) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2013 Segment | Oct. 04, 2010 MVSD [Member] | Oct. 04, 2010 SISD [Member]
Goodwill [Line Items] |  |  |
Number of reportable segments | 2 |  |
Fair value in excess to carrying value |  | 208.00% | 119.00%

X
- Definition Fair value in excess to carrying value. + References No definition available. + Details
Name: | cgnx_FairValueInExcessToCarryingValue
Namespace Prefix: | cgnx_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Number of reporting units for goodwill allocation. + References No definition available. + Details
Name: | cgnx_NumberOfReportingUnitsForGoodwillAllocation
Namespace Prefix: | cgnx_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_GoodwillLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration