XML 69 R35.htm IDEA: XBRL DOCUMENT v3.8.0.1
Income Taxes (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2018
Dec. 31, 2017
Dec. 31, 2016
Dec. 31, 2015
Income Taxes [Abstract]        
Reduction in deferred tax asset   $ 6,800    
Deferred liabilities [Abstract]        
Available-for-sale securities   0 $ (761)  
Total deferred tax liabilities   0 (761)  
Deferred tax assets [Abstract]        
Net operating loss carryforwards   11,414 11,730  
Research and development credit carryforwards   2,141 1,765  
Patents and fixed assets   268 179  
Stock-based compensation and accrued payroll   1,260 1,041  
Valuation Allowance   (15,083) (13,954)  
Total deferred tax assets   0 761  
Net deferred tax asset (liability)   $ 0 $ 0  
Income Tax Reconciliation [Abstract]        
Computed tax benefit at federal statutory rate   34.00% 34.00% 34.00%
Re-rate of federal net deferred tax assets   (35.00%) 0.00% 0.00%
Permanent differences   (8.00%) (1.00%) (9.00%)
State tax benefit   3.00% 2.00% 15.00%
Research and development credits   1.00% 2.00% 2.00%
Other   0.00% 7.00% 3.00%
Adjusted basis for available-for-sale-securities   11.00% 0.00% 0.00%
Change in valuation allowance   (6.00%) (44.00%) (45.00%)
Total   0.00% 0.00% 0.00%
Class of Stock [Line Items]        
Company share in market transactions (in shares)   31,452,000 28,737,000  
Change in valuation allowance   $ 1,100 $ 5,100  
Percentage of change in ownership   50.00%    
Period in which change of ownership for a specified percentage should occur   3 years    
Research Tax Credit Carryforward [Member]        
Tax Credit Carryforward [Line Items]        
Tax credit carryforwards, federal   $ 1,000    
Tax credit carryforwards, state   $ 1,100    
Research Tax Credit Carryforward [Member] | Minimum [Member]        
Tax Credit Carryforward [Line Items]        
Tax credit carryforwards, expiration date, federal   Dec. 31, 2030    
Research Tax Credit Carryforward [Member] | Maximum [Member]        
Tax Credit Carryforward [Line Items]        
Tax credit carryforwards, expiration date, federal   Dec. 31, 2037    
Plan [Member]        
Income Tax Reconciliation [Abstract]        
Computed tax benefit at federal statutory rate 21.00%      
Federal [Member]        
Operating Loss Carryforwards [Line Items]        
Net operating loss carryforwards   $ 47,800    
Federal [Member] | Minimum [Member]        
Operating Loss Carryforwards [Line Items]        
Operating loss carryforwards, expiration date   Dec. 31, 2030    
Federal [Member] | Maximum [Member]        
Operating Loss Carryforwards [Line Items]        
Operating loss carryforwards, expiration date   Dec. 31, 2037    
State [Member]        
Operating Loss Carryforwards [Line Items]        
Net operating loss carryforwards   $ 15,600    
State [Member] | Minimum [Member]        
Operating Loss Carryforwards [Line Items]        
Operating loss carryforwards, expiration date   Dec. 31, 2029    
State [Member] | Maximum [Member]        
Operating Loss Carryforwards [Line Items]        
Operating loss carryforwards, expiration date   Dec. 31, 2037    
BioTime, Inc. [Member]        
Class of Stock [Line Items]        
Company share in market transactions (in shares)   266,442 0 259,712
Investors taxable loss   $ (301)   $ (397)