| 6. Goodwill and Indefinite-Lived Intangible Assets (Details Narrative) (USD $) | 12 Months Ended | |
|---|---|---|
| Dec. 31, 2014 | Dec. 31, 2013 | |
| Indefinite-lived Intangible Assets [Line Items] | ||
| Carrying value of indefinite-lived intangible asset | $ 9,754,857us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill | $ 10,318,001us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill | 
| Onco Hist [Member] | ||
| Indefinite-lived Intangible Assets [Line Items] | ||
| Fair value of indefinite-lived intangible asset | 14,610,000us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwillFairValueDisclosure / us-gaap_IndefiniteLivedIntangibleAssetsByMajorClassAxis = xbio_OncoHistMember | 10,400,000us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwillFairValueDisclosure / us-gaap_IndefiniteLivedIntangibleAssetsByMajorClassAxis = xbio_OncoHistMember | 
| Carrying value of indefinite-lived intangible asset | 9,750,000us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill / us-gaap_IndefiniteLivedIntangibleAssetsByMajorClassAxis = xbio_OncoHistMember | 10,320,000us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill / us-gaap_IndefiniteLivedIntangibleAssetsByMajorClassAxis = xbio_OncoHistMember | 
| Impairment of indefinite-lived intangible asset | $ 0us-gaap_ImpairmentOfIntangibleAssetsIndefinitelivedExcludingGoodwill / us-gaap_IndefiniteLivedIntangibleAssetsByMajorClassAxis = xbio_OncoHistMember | $ 0us-gaap_ImpairmentOfIntangibleAssetsIndefinitelivedExcludingGoodwill / us-gaap_IndefiniteLivedIntangibleAssetsByMajorClassAxis = xbio_OncoHistMember | 
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- Definition Amount of impairment loss resulting from write-down of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit to fair value. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition Amount of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition Fair value portion of assets, excluding financial assets and goodwill, that lack physical substance, having a projected indefinite period of benefit. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Details 
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