XML 25 R42.htm IDEA: XBRL DOCUMENT v2.4.1.9
PROPERTY AND EQUIPMENT, NET (Details) (USD $)
12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Property and Equipment [Line Items]    
Property and equipment, gross $ 10,069,718us-gaap_PropertyPlantAndEquipmentGross $ 10,069,718us-gaap_PropertyPlantAndEquipmentGross
Accumulated depreciation (8,861,743)us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment (8,269,412)us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment
Property and equipment, net 1,207,975us-gaap_PropertyPlantAndEquipmentNet 1,800,306us-gaap_PropertyPlantAndEquipmentNet
Depreciation expense 592,331us-gaap_Depreciation 643,575us-gaap_Depreciation
Net book value of assets sold 0ztho_SignificantAcquisitionsAndDisposalsNetBookValueOfAssetsSold 2,084ztho_SignificantAcquisitionsAndDisposalsNetBookValueOfAssetsSold
Cash proceeds from sale of assets   750us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment
Gain (Loss) on sale   (1,334)us-gaap_GainLossOnSaleOfPropertyPlantEquipment
Production, Engineering and Other Equipment [Member]    
Property and Equipment [Line Items]    
Property and equipment, gross 6,422,110us-gaap_PropertyPlantAndEquipmentGross
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= us-gaap_EquipmentMember
6,422,110us-gaap_PropertyPlantAndEquipmentGross
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= us-gaap_EquipmentMember
Leasehold Improvements [Member]    
Property and Equipment [Line Items]    
Property and equipment, gross 2,904,188us-gaap_PropertyPlantAndEquipmentGross
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= us-gaap_LeaseholdImprovementsMember
2,904,188us-gaap_PropertyPlantAndEquipmentGross
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= us-gaap_LeaseholdImprovementsMember
Office Equipment and Furniture [Member]    
Property and Equipment [Line Items]    
Property and equipment, gross 603,182us-gaap_PropertyPlantAndEquipmentGross
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= us-gaap_OfficeEquipmentMember
603,182us-gaap_PropertyPlantAndEquipmentGross
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= us-gaap_OfficeEquipmentMember
Computer Equipment and Related Software [Member]    
Property and Equipment [Line Items]    
Property and equipment, gross $ 140,238us-gaap_PropertyPlantAndEquipmentGross
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= us-gaap_ComputerEquipmentMember
$ 140,238us-gaap_PropertyPlantAndEquipmentGross
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= us-gaap_ComputerEquipmentMember