Quarterly report pursuant to Section 13 or 15(d)

Summary of Significant Accounting Policies - Narrative (Details)

v3.21.2
Summary of Significant Accounting Policies - Narrative (Details)
 3 Months Ended 9 Months Ended 12 Months Ended
Jun. 18, 2021
USD ($)
$ / shares
shares
Mar. 17, 2020
USD ($)
Dec. 19, 2019
recipient
shares
Sep. 30, 2021
USD ($)
shares
Sep. 30, 2020
USD ($)
Sep. 30, 2021
USD ($)
shares
Sep. 30, 2020
USD ($)
Dec. 31, 2020
USD ($)
award_type
shares
Dec. 31, 2019
business
Dec. 31, 2014
award_type
Jun. 16, 2021
shares
Jan. 13, 2021
$ / shares
shares
Mar. 07, 2019
shares
Debt Instrument [Line Items]                          
Proceeds from Merger and PIPE financing, net of cash paid $ 157,383,000         $ 157,383,000 $ 0            
Net cash provided by (used in) operating activities           (59,144,000) 3,625,000            
Restricted cash       $ 100,000   100,000   $ 1,500,000          
Repayment of drawdown on line of credit             4,672,000            
Cash equivalents       0   $ 0   0          
Holdback period of cash from shareholders from business acquisition           1 year 1 month 15 days              
Allowance for doubtful accounts       1,300,000   $ 1,300,000   1,300,000          
Accounts receivable recoveries       0 $ 0 0 0            
Bad debt expense       100,000 (400,000) 110,000 624,000            
Accounts receivable, writeoffs       100,000 100,000 100,000 300,000            
Goodwill impairment charge       0 0 0 0            
Impairment of long-lived assets       0 0 $ 0 0            
Deferred sales commission, amortization period           5 years              
Amortization of deferred sales commissions       500,000 300,000 $ 1,368,000 887,000            
Deferred sales commission, impairment loss       0 0 0 0            
Capitalized advertising       0 0 0 0            
Advertising expense       300,000 200,000 400,000 400,000            
Capitalized software development costs related to internal-use software       0 0 0 0            
Number of incentive award types | award_type                   2      
Stock-based compensation expense       $ 1,180,000 157,000 $ 1,458,000 470,000            
Number of warrants outstanding (in shares) | shares       13,333,333   13,333,333              
Number of common shares called by each warrant (in shares) | shares 1                     1  
Exercise price (in dollars per share) | $ / shares $ 11.50                     $ 11.50  
Warrant liability       $ 1,333,000   $ 1,333,000   $ 0          
Value Creation Incentive Plan and Option-Based Incentive Plan                          
Debt Instrument [Line Items]                          
Number of incentive award types | award_type               2          
Compensation expense related to repurchases       (100,000) 100,000   300,000            
Total value of incentive plans       $ 68,700,000   68,700,000   $ 21,200,000          
Value of vested incentive plans           68,700,000   13,700,000          
Awards deemed probably of repurchase               $ 300,000          
Stock-based compensation expense           $ 68,400,000              
Value Creation Incentive Plan                          
Debt Instrument [Line Items]                          
Allocated percentage for distribution           15.00%              
Granted percentage           9.30%   9.30%          
Vested percentage           9.30%   5.70%          
Vesting period                   5 years      
Option-Based Incentive Plan                          
Debt Instrument [Line Items]                          
Number of potential award units (in shares) | shares       2,000,000   2,000,000              
Number of award units granted (in shares) | shares           1,800,000   1,800,000          
Number of award units vested (in shares) | shares           1,800,000   1,500,000          
Vesting period                   5 years      
Value Creation Incentive Plan and Option-Based Incentive Plan, Cash Portion                          
Debt Instrument [Line Items]                          
Total value of incentive plans       $ 200,000   $ 200,000              
Value Creation Incentive Plan and Option-Based Incentive Plan, Stock Portion                          
Debt Instrument [Line Items]                          
Total value of incentive plans       $ 1,100,000   $ 1,100,000              
2021 Equity Incentive Plan                          
Debt Instrument [Line Items]                          
Number of potential award units (in shares) | shares                     9,770,000    
Increase in common stock reserved for issuance as a percentage of shares outstanding       5.00%   5.00%              
Company One                          
Debt Instrument [Line Items]                          
Number of businesses acquired | business                 1        
Company Two and Company Three                          
Debt Instrument [Line Items]                          
Number of businesses acquired | business                 2        
Private Warrants | Crescent                          
Debt Instrument [Line Items]                          
Warrants issued (in shares) | shares                         7,000,000
Public Warrant                          
Debt Instrument [Line Items]                          
Number of warrants outstanding (in shares) | shares                       12,500,000  
Exercise price (in dollars per share) | $ / shares $ 0.01                        
Public Warrant | Crescent                          
Debt Instrument [Line Items]                          
Warrants issued (in shares) | shares                         12,500,000
Forward Purchase Warrant                          
Debt Instrument [Line Items]                          
Warrants issued (in shares) | shares 833,333                     833,333  
Number of warrants outstanding (in shares) | shares                       833,333  
Warrant liability $ 2,000,000     $ 1,300,000   $ 1,300,000              
Minimum                          
Debt Instrument [Line Items]                          
Typical contract term           1 year              
Payment term           10 days              
Maximum                          
Debt Instrument [Line Items]                          
Typical contract term           3 years              
Payment term           60 days              
MIUs                          
Debt Instrument [Line Items]                          
Stock-based compensation expense       139,000 157,000 $ 417,000 470,000            
Share-based compensation expense, amortization period           2 years 1 month 6 days              
MIUs | Management Incentive Unit Program                          
Debt Instrument [Line Items]                          
Vesting period                 5 years        
Percent vested each anniversary                 20.00%        
Number of units issued (in shares) | shares     3,518,096                    
Number of recipients | recipient     12                    
Share-based compensation expense, amortization period           5 years              
RSUs | Employee                          
Debt Instrument [Line Items]                          
Stock-based compensation expense       924,000 0 $ 924,000 0            
Share-based compensation expense, amortization period           3 years 9 months 3 days              
RSUs | Nonemployee                          
Debt Instrument [Line Items]                          
Stock-based compensation expense       3,000 0 $ 3,000 0            
Share-based compensation expense, amortization period           3 years 8 months 19 days              
RSUs | 2021 Equity Incentive Plan | Nonemployee                          
Debt Instrument [Line Items]                          
Vesting period           4 years              
RSUs | Minimum | 2021 Equity Incentive Plan | Employee                          
Debt Instrument [Line Items]                          
Vesting period           3 years              
RSUs | Maximum | 2021 Equity Incentive Plan | Employee                          
Debt Instrument [Line Items]                          
Vesting period           6 years              
PSUs | Employee                          
Debt Instrument [Line Items]                          
Stock-based compensation expense       $ 114,000 $ 0 $ 114,000 $ 0            
Share-based compensation expense, amortization period           10 years 8 months 1 day              
PSUs | Minimum | 2021 Equity Incentive Plan                          
Debt Instrument [Line Items]                          
Vesting period           4 years              
PSUs | Maximum | 2021 Equity Incentive Plan                          
Debt Instrument [Line Items]                          
Vesting period           6 years              
Accounts Payable Benchmark | Supplier Concentration Risk | Two Largest Suppliers                          
Debt Instrument [Line Items]                          
Concentration risk, percentage           43.00%   55.00%          
Revenue Benchmark | Professional Service | Professional Services                          
Debt Instrument [Line Items]                          
Concentration risk, percentage           2.00%              
Revolving Credit Facility | Amended Credit Facility Effective February 2018 | PNC Bank | Line of Credit                          
Debt Instrument [Line Items]                          
Repayment of drawdown on line of credit   $ 4,700,000