Note 13 - Intellectual Property - License Agreements (Details Textual) $ in Millions	12 Months Ended
Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Number of License Agreements	3
Royalty Expense	$ 6.8	$ 5.1	$ 4.8
License Costs	$ 0.2	$ 0.2	$ 0.1
Aggregate Royalty Rate, Percent of Gross Product and Service Revenue	8.00%	8.00%	10.00%

The aggregate royalty rate paid by the Company as a percentage of the gross product and service revenue of the Company.

No definition available.

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Namespace Prefix:	oxfd_
Data Type:	num:percentItemType
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Period Type:	duration

- Definition

The number of license agreements by which the Company has secured patent rights to make, use and sell the T-SPOT.TB test.

+ References

No definition available.

+ Details

Name:	oxfd_NumberOfLicenseAgreements
Namespace Prefix:	oxfd_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Costs incurred and are directly related to generating license revenue. Licensing arrangements include, but are not limited to, rights to use a patent, copyright, technology, manufacturing process, software or trademark.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.2(e))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

+ Details

Name:	us-gaap_LicenseCosts
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of expense related to royalty payments under a contractual arrangement such as payment for mineral and drilling rights and use of technology or intellectual property.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.3)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

+ Details

Name:	us-gaap_RoyaltyExpense
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration