Annual report pursuant to Section 13 and 15(d)

11. Employee Benefit Plans (Details Narrative)

v2.4.1.9
11. Employee Benefit Plans (Details Narrative) (USD $)
12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
401k Plan [Member]    
Contribution to 401k plan $ 31,738us-gaap_DefinedBenefitPlanContributionsByEmployer
/ us-gaap_DefinedContributionPlanNameAxis
= xbio_Plan401KMember
$ 0us-gaap_DefinedBenefitPlanContributionsByEmployer
/ us-gaap_DefinedContributionPlanNameAxis
= xbio_Plan401KMember
UK Plan [Member]    
Contribution to 401k plan $ 108,439us-gaap_DefinedBenefitPlanContributionsByEmployer
/ us-gaap_DefinedContributionPlanNameAxis
= xbio_UKPlanMember
$ 129,353us-gaap_DefinedBenefitPlanContributionsByEmployer
/ us-gaap_DefinedContributionPlanNameAxis
= xbio_UKPlanMember