Capital Stock - Series H Preferred Stock Transactions - Additional Information (Detail) - USD ($)
 3 Months Ended 6 Months Ended 12 Months Ended
Apr. 14, 2015
Oct. 31, 2014
Oct. 14, 2014
Sep. 10, 2014
Aug. 06, 2014
Jun. 26, 2014
May. 29, 2014
Mar. 12, 2013
Jan. 22, 2013
Mar. 09, 2012
Jun. 30, 2015
Jun. 30, 2015
Dec. 31, 2014
Dec. 31, 2013
Aug. 31, 2013
Class of Stock [Line Items]                              
Warrants outstanding converted into common stock               16,667 33,750       127,508,118 45,650,654  
Warrants exercisable price               $ 30.00 $ 30.00           $ 0.25
Warrant term               5 years 5 years            
Convertible preferred stock, conversion price                   $ 60.00          
Number of shares of common stock sold       29,630 40,000 36,667 22,223 33,334 67,500            
Common stock, shares authorized                     720,000,000 720,000,000 720,000,000 300,000,000  
From exercises of warrants, amount                       $ 612,000 $ 444,000    
Common Stock [Member]                              
Class of Stock [Line Items]                              
Number of shares of common stock sold                         184,000 [1] 37,991,000  
Issuance of common stock from conversion of preferred stock, shares                 8,000,000   162,000 162,000 [1] 60,000 [1] 8,000,000  
Placement Agent [Member]                              
Class of Stock [Line Items]                              
Warrants exercisable price                     $ 13.815 $ 13.815 $ 0.0921    
Warrant term                       5 years 6 months 5 years 6 months    
Date of placement agency engagement letter                       Sep. 23, 2014 Sep. 23, 2014    
Placement agent fee                       $ 200,000 $ 200,000    
From exercises of warrants, amount                       62,045 9,306,654    
Reimbursement of fees and expenses                       $ 50,000 $ 50,000    
Securities Purchase Agreement [Member] | Series A Warrants [Member]                              
Class of Stock [Line Items]                              
Warrants exercisable price   $ 0.0576 $ 6.72                        
Securities Purchase Agreement [Member] | Series B Warrants [Member]                              
Class of Stock [Line Items]                              
Warrants exercisable price   0.0576 6.72                        
Securities Purchase Agreement [Member] | Series C warrants [Member]                              
Class of Stock [Line Items]                              
Warrants exercisable price   0.0576 6.72                        
Previously Reported [Member]                              
Class of Stock [Line Items]                              
Warrants outstanding converted into common stock               2,500,000 5,062,500            
Warrants exercisable price               $ 0.20 $ 0.20            
Number of shares of common stock sold       4,444,445 6,000,000 5,500,000 3,333,333 5,000,000 10,125,000            
Previously Reported [Member] | Common Stock [Member]                              
Class of Stock [Line Items]                              
Number of shares of common stock sold [1]                         27,598,000    
From exercises of warrants, amount                         $ 6,000    
Issuance of common stock from conversion of preferred stock, shares [1]                         9,000,000    
Series H Preferred Stock [Member]                              
Class of Stock [Line Items]                              
Conversion of stock, shares converted                     1,104.84   518.40    
Series H Preferred Stock [Member] | Securities Purchase Agreement [Member]                              
Class of Stock [Line Items]                              
Convertible preferred stock, conversion price   $ 0.0576 $ 6.72                        
Purchasers [Member] | Securities Purchase Agreement [Member]                              
Class of Stock [Line Items]                              
Common stock, shares authorized                     720,000,000 720,000,000 720,000,000    
Percentage of common stock resale                       100.00% 100.00%    
Purchasers [Member] | Securities Purchase Agreement [Member] | Private placement [Member]                              
Class of Stock [Line Items]                              
Aggregate initial gross proceeds     $ 2,500,000                        
Purchasers [Member] | Securities Purchase Agreement [Member] | Private placement [Member] | Series A Warrants [Member]                              
Class of Stock [Line Items]                              
Warrants outstanding converted into common stock     258,519                        
Warrants exercisable price     $ 13.8150                        
Warrant term     5 years 6 months                        
Purchasers [Member] | Securities Purchase Agreement [Member] | Private placement [Member] | Series B Warrants [Member]                              
Class of Stock [Line Items]                              
Warrants outstanding converted into common stock     258,519                        
Warrants exercisable price $ 11.2500   $ 9.6705                        
Warrant term     6 months                        
Warrants, termination date Jun. 20, 2015                            
Purchasers [Member] | Securities Purchase Agreement [Member] | Private placement [Member] | Series C warrants [Member]                              
Class of Stock [Line Items]                              
Warrants outstanding converted into common stock     258,519                        
Warrants exercisable price     $ 9.6705                        
Warrant term     12 months                        
Purchasers [Member] | Previously Reported [Member] | Securities Purchase Agreement [Member] | Private placement [Member] | Series A Warrants [Member]                              
Class of Stock [Line Items]                              
Warrants outstanding converted into common stock     38,777,726                        
Warrants exercisable price     $ 0.0921                        
Purchasers [Member] | Previously Reported [Member] | Securities Purchase Agreement [Member] | Private placement [Member] | Series B Warrants [Member]                              
Class of Stock [Line Items]                              
Warrants outstanding converted into common stock     38,777,726                        
Warrants exercisable price     $ 0.06447                        
Purchasers [Member] | Previously Reported [Member] | Securities Purchase Agreement [Member] | Private placement [Member] | Series C warrants [Member]                              
Class of Stock [Line Items]                              
Warrants outstanding converted into common stock     38,777,726                        
Warrants exercisable price     $ 0.06447                        
Purchasers [Member] | Series H Preferred Stock [Member] | Securities Purchase Agreement [Member]                              
Class of Stock [Line Items]                              
Percentage of common stock resale                       200.00% 200.00%    
Purchasers [Member] | Series H Preferred Stock [Member] | Securities Purchase Agreement [Member] | Private placement [Member]                              
Class of Stock [Line Items]                              
Preferred stock, par value per share     0.001                        
Preferred stock, stated value per share     $ 1,000                        
Convertible preferred stock, common stock shares issuable upon conversion     258,519                        
Convertible preferred stock, conversion price     $ 9.6705                        
Purchasers [Member] | Series H Preferred Stock [Member] | Securities Purchase Agreement [Member] | Private placement [Member] | Series H One [Member]                              
Class of Stock [Line Items]                              
Number of shares of common stock sold     2,000                        
Purchasers [Member] | Series H Preferred Stock [Member] | Securities Purchase Agreement [Member] | Private placement [Member] | Series H Two [Member]                              
Class of Stock [Line Items]                              
Number of shares of common stock sold     500                        
Purchasers [Member] | Series H Preferred Stock [Member] | Previously Reported [Member] | Securities Purchase Agreement [Member] | Private placement [Member]                              
Class of Stock [Line Items]                              
Convertible preferred stock, common stock shares issuable upon conversion     38,777,726                        
Convertible preferred stock, conversion price     $ 0.06447                        
[1] See Note 1, "Reverse Stock Split"