General form of registration statement for all companies including face-amount certificate companies

Subsequent events (FY) (Details)

v3.21.1
Subsequent events (FY) (Details)
 1 Months Ended 3 Months Ended 8 Months Ended 12 Months Ended
Jan. 22, 2021
USD ($)
$ / shares
shares
Jan. 06, 2021
USD ($)
Mar. 30, 2021
USD ($)
$ / shares
shares
Mar. 31, 2021
USD ($)
$ / shares
shares
Dec. 31, 2020
$ / shares
shares
Mar. 31, 2020
USD ($)
Dec. 31, 2019
$ / shares
shares
Dec. 31, 2020
USD ($)
$ / shares
shares
Dec. 31, 2019
USD ($)
$ / shares
Nov. 30, 2020
$ / shares
Sep. 30, 2020
$ / shares
Jul. 20, 2020
$ / shares
Jun. 30, 2020
$ / shares
Jun. 24, 2020
$ / shares
Mar. 17, 2020
$ / shares
Dec. 19, 2019
$ / shares
Nov. 04, 2019
$ / shares
Dec. 12, 2018
shares
Subsequent Event [Line Items]                                    
Proceeds from shares issued               $ 18,053,000 $ 15,826,000                  
Common stock, par value (in dollars per share) | $ / shares       $ 0.001 $ 0.001   $ 0.001 $ 0.001 $ 0.001                  
Number of warrants in each unit (in shares) | shares                                   1
Term of warrants                   72 months       84 months   24 months 24 months  
Number of shares of common stock issuable per warrant (in shares) | shares                                   0.50
Warrants, exercise price (in dollars per share) | $ / shares                   $ 1.00 $ 0.65 $ 1.05 $ 0.75 $ 1.25 $ 1.62 $ 5.00 $ 5.00  
Warrants exercised (in shares) | shares       1,839,275 1,687,690   1,144,999 1,937,690                    
Proceeds from warrant exercises       $ 1,310,000   $ 0   $ 1,048,000 $ 4,007,000                  
Stock options granted (in shares) | shares               1,050,000                    
Forecast                                    
Subsequent Event [Line Items]                                    
Warrants, exercise price (in dollars per share) | $ / shares     $ 4.25                              
Warrants, reduced exercise price (in dollars per share) | $ / shares     $ 1.25                              
Warrants exercised (in shares) | shares     1,047,609                              
Proceeds from warrant exercises     $ 1,300,000                              
Stock options granted (in shares) | shares       5,479,000                            
Private Placement                                    
Subsequent Event [Line Items]                                    
Sale of stock, consideration $ 4,100,000                                  
Sale of stock, price (in dollars per share) | $ / shares $ 1.25                                  
Number of shares of stock in each unit (in shares) | shares 1                                  
Common stock, par value (in dollars per share) | $ / shares $ 0.001                                  
Number of warrants in each unit (in shares) | shares 1                                  
Number of shares of common stock issuable per warrant (in shares) | shares 1                                  
Private Placement | Officers and directors                                    
Subsequent Event [Line Items]                                    
Proceeds from shares issued $ 1,600,000                                  
Old Plank Trail Community Bank, N.A. | Term Loan                                    
Subsequent Event [Line Items]                                    
Maximum borrowing capacity   $ 6,000,000.0                                
Old Plank Trail Community Bank, N.A. | Line of credit                                    
Subsequent Event [Line Items]                                    
Maximum borrowing capacity   $ 6,000,000.0                                
Fixed charge coverage ratio   1.25                                
Subsequent Event | Private Placement                                    
Subsequent Event [Line Items]                                    
Sale of stock, consideration $ 4,100,000                                  
Sale of stock, price (in dollars per share) | $ / shares $ 1.25                                  
Number of shares of stock in each unit (in shares) | shares 1                                  
Common stock, par value (in dollars per share) | $ / shares $ 0.001                                  
Number of warrants in each unit (in shares) | shares 1                                  
Term of warrants 6 years                                  
Number of shares of common stock issuable per warrant (in shares) | shares 1                                  
Gross proceeds received $ 3,100,000                                  
Gross proceeds receivable $ 1,000,000                                  
Warrants, exercise price (in dollars per share) | $ / shares $ 1.45                                  
Subsequent Event | Private Placement | Officers and directors                                    
Subsequent Event [Line Items]                                    
Proceeds from shares issued $ 1,600,000                                  
Subsequent Event | Old Plank Trail Community Bank, N.A. | Term Loan                                    
Subsequent Event [Line Items]                                    
Maximum borrowing capacity   $ 6,000,000.0                                
Subsequent Event | Old Plank Trail Community Bank, N.A. | Line of credit                                    
Subsequent Event [Line Items]                                    
Maximum borrowing capacity   $ 6,000,000.0                                
Fixed charge coverage ratio   1.25