Annual report pursuant to Section 13 and 15(d)

Fair Value Measurements (Narrative) (Details)

v3.24.1
Fair Value Measurements (Narrative) (Details)
$ / shares in Units, $ in Thousands
 1 Months Ended 12 Months Ended
Oct. 04, 2023
USD ($)
Dec. 16, 2022
USD ($)
Oct. 11, 2022
USD ($)
item
$ / shares
shares
Nov. 30, 2023
USD ($)
item
$ / shares
shares
Oct. 31, 2023
USD ($)
$ / shares
shares
Feb. 28, 2023
USD ($)
Dec. 31, 2023
USD ($)
$ / shares
Dec. 31, 2022
USD ($)
Jul. 31, 2023
$ / shares
Jun. 13, 2023
$ / shares
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]                    
Estimated fair value of retained investment             $ 2,600      
Sale of stock, net proceeds       $ 8,900 $ 10,000          
Gain (loss) on common stock warrant liabilities             (4,424) $ (1,129)    
Common stock, value             15 7    
Warrant expiration term       5 years            
Common stock warrant liabilities             886 13,869    
Number of common stock (in units) | item       1            
Number of warrants (in units) | item       1            
Number of shares called by warrants | shares       1            
Exercise price of warrants | $ / shares       $ 1.70           $ 8.136
Proceeds from issuance of common stock for at-the-market offering, net             $ 2,041 6,053    
Sale of National Holding's stock, proceeds received       $ 8,900 $ 10,000          
Stock price                    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]                    
Retained investment, deconsolidated subsidiary, measurement input | $ / shares             0.328      
Risk-free interest rate                    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]                    
Retained investment, deconsolidated subsidiary, measurement input             0.037      
Volatility                    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]                    
Retained investment, deconsolidated subsidiary, measurement input             0.80      
Discount for lack of marketability                    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]                    
Retained investment, deconsolidated subsidiary, measurement input             0.397      
December 2022 Offering                    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]                    
Exercise price of warrants | $ / shares         $ 4.075          
Checkpoint Common Stock Warrants                    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]                    
Sale of stock, net proceeds         $ 10,000          
Net proceeds         $ 11,100          
Warrants issued | shares         6,325,354          
Exercise price of warrants | $ / shares         $ 4.075          
Stock offering, aggregate fees paid         $ 1,100          
Sale of National Holding's stock, proceeds received         $ 10,000          
Checkpoint Common Stock Warrants | Minimum                    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]                    
Exercise price of warrants | $ / shares         $ 1.76          
Checkpoint Common Stock Warrants | Common Stock Warrant                    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]                    
Warrants issued | shares         6,325,354          
Exercise price of warrants | $ / shares         $ 1.51          
Checkpoint Common Stock Warrants | Common Stock Warrant | Minimum                    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]                    
Exercise price of warrants | $ / shares                 $ 2.82  
Checkpoint Common Stock Warrants | Common Stock Warrant | Maximum                    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]                    
Exercise price of warrants | $ / shares                 $ 5.00  
Checkpoint Common Stock Warrants | Common Stock and Pre-funded Warrants                    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]                    
Sale of stock, net proceeds           $ 6,700        
Net proceeds   $ 0                
Proceeds from issuance of common stock for at-the-market offering, net           7,500        
Stock offering, aggregate fees paid           800        
Sale of National Holding's stock, proceeds received           $ 6,700        
Checkpoint Common Stock Warrants | 2022 Director Offering                    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]                    
Sale of stock, net proceeds   6,700                
Sale of National Holding's stock, proceeds received   $ 6,700                
Checkpoint Common Stock Warrants | February 2023 Offering                    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]                    
Exercise price of warrants | $ / shares         $ 5.00          
Avenue                    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]                    
Warrant expiration term       5 years            
Shares issued | shares     3,636,365              
Number of common stock (in units) | item     1 1            
Number of warrants (in units) | item     1              
Number of shares called by warrants | shares     1              
Proceeds from issuance of common stock for at-the-market offering, net     $ 10,300 $ 5,000            
Avenue | Pre funded warrants                    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]                    
Exercise price of warrants | $ / shares     $ 0.0001              
Unit Price Per Share | $ / shares     3.2999              
Avenue | Common Stock and Pre-funded Warrants                    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]                    
Unit Price Per Share | $ / shares     $ 3.30              
Common Stock Warrant | Checkpoint Common Stock Warrants                    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]                    
Issuance of Warrants             $ 6,300 7,640    
Gain (loss) on common stock warrant liabilities $ 7,700           (7,924) 3,252    
Common stock warrant liabilities             125 11,170    
Common Stock Warrant | Checkpoint Common Stock Warrants | 2022 Director Offering                    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]                    
Gain (loss) on common stock warrant liabilities 1,200                  
Common Stock Warrant | Checkpoint Common Stock Warrants | February 2023 Offering                    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]                    
Gain (loss) on common stock warrant liabilities $ 1,100                  
Common Stock Warrant | Avenue                    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]                    
Issuance of Warrants     $ 8,278       2,235 8,278    
Gain (loss) on common stock warrant liabilities     (5,669)       (4,258) (5,669)    
Common stock warrant liabilities     $ 2,609       586      
Placement Agent Warrants | Checkpoint Common Stock Warrants                    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]                    
Issuance of Warrants               278    
Warrants issued | shares         379,521          
Exercise price of warrants | $ / shares         $ 2.20          
Placement Agent Warrants | Urica                    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]                    
Issuance of Warrants             33 90    
Gain (loss) on common stock warrant liabilities             52      
Contingent Payment Warrants | Urica                    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]                    
Common stock warrant liabilities             $ 200 $ 100