XML 22 R37.htm IDEA: XBRL DOCUMENT v2.4.1.9
Income Taxes - Additional Information (Detail) (USD $)
 12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2011
Income Tax Disclosure [Abstract]      
Provision for income taxes $ 0us-gaap_IncomeTaxExpenseBenefit $ 0us-gaap_IncomeTaxExpenseBenefit  
Increase in valuation allowance 700,000us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount 1,000,000us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount  
Valuation allowance for operating loss and tax credit carryforwards 0nanx_OperatingLossAndTaxCreditCarryForwardValuationAllowance 0nanx_OperatingLossAndTaxCreditCarryForwardValuationAllowance  
Net operating loss carryforwards 80,000,000us-gaap_OperatingLossCarryforwards    
Capital loss carryforwards   $ 300,000nanx_CapitalLossCarryforwards  
Capital loss carryforwards expiration period   2014  
Capital loss carryforwards expiration period start 2018    
Capital loss carryforwards expiration period end 2034    
Period for suspension of net operating loss carryforwards     4 years
Extension of the term of net loss carryforwards     4 years