Annual report pursuant to Section 13 and 15(d)

Annual report pursuant to Section 13 and 15(d)

Debt - Narrative (Detail)

v3.20.4
Debt - Narrative (Detail)
1 Months Ended 12 Months Ended
May 04, 2020
USD ($)
day
Rate
Jun. 27, 2019
USD ($)
May 31, 2019
USD ($)
Dec. 31, 2020
USD ($)
Rate
shares
Dec. 31, 2019
USD ($)
Dec. 31, 2018
USD ($)
Dec. 31, 2020
USD ($)
Dec. 31, 2020
Dec. 31, 2020
$ / shares
May 04, 2020
USD ($)
May 04, 2020
May 04, 2020
$ / shares
Line of Credit Facility [Line Items]                        
Issuance of common stock, net     $ 171,100,000 $ 20,310,000 $ 11,202,000 $ 9,023,000            
Dilutive effect of Convertible Notes (in shares) | shares       3,722,504                
Ownership of convertible notes (as a percent) 25.00%                      
Equity component of Convertible Senior Notes due 2025       $ 30,912,000                
Tax liability related to Convertible Senior Notes due 2025       7,504,000                
Proceeds from issuance of convertible debt, net of issuance costs       194,466,000 0 0            
Debt issuance costs             $ (538,000)          
Loss on extinguishment of debt       $ 1,400,000 $ 1,018,000 $ 0            
Weighted average interest rate of debt (as a percent)         4.64%     4.91%        
Over-Allotment Option                        
Line of Credit Facility [Line Items]                        
Issuance of common stock, net $ 194,500,000                      
Convertible Debt                        
Line of Credit Facility [Line Items]                        
Proceeds from issuance of convertible debt, net of issuance costs $ 97,500,000                      
Term Loan                        
Line of Credit Facility [Line Items]                        
Debt issuance costs         $ (700,000)              
Loss on extinguishment of debt         1,400,000              
1.25% Convertible Senior Notes | Convertible Debt                        
Line of Credit Facility [Line Items]                        
Stated interest rate (as a percent) 1.25%     1.25%       1.25%     1.25%  
Fair value of debt             320,900,000          
Debt instrument, face amount                   $ 201,300,000    
Discount on principal amount (as a percent) | Rate 97.00%                      
Discount on shares                   $ 6,900,000    
Threshold trading days | day 20                      
Consecutive trading days | day 30                      
Conversion price on applicable trading day (as a percent) 130.00%                      
Convertible Notes, conversion ratio | Rate 2.75198%                      
Convertible Notes, conversion price (in dollars per share) | $ / shares                 $ 53.84     $ 36.34
Convertible debt, if converted, value in excess of principal $ 96,900,000                      
Redemption price of principal (as a percent) 100.00%                      
Interest expense, contractual coupon interest       $ 1,700,000                
Interest expense, accretion of debt discount       4,400,000                
Interest expense, amortization of debt issuance costs       $ 70,000.00                
Effective interest rate on Convertible Notes (as a percent)       5.50%                
Carrying amount of equity component             23,400,000          
Debt issuance costs         0   $ (538,000)          
1.25% Convertible Senior Notes | Convertible Debt | Debt Instrument, Redemption, Period One                        
Line of Credit Facility [Line Items]                        
Threshold trading days | day 20                      
Consecutive trading days | day 30                      
Conversion price on applicable trading day (as a percent) 130.00%                      
1.25% Convertible Senior Notes | Convertible Debt | Debt Instrument, Redemption, Period Two                        
Line of Credit Facility [Line Items]                        
Threshold trading days | day 5                      
Consecutive trading days | day 5                      
Principal amount priced to investors (as a percent) | Rate 98.00%                      
New Credit Agreement | Federal Funds Rate                        
Line of Credit Facility [Line Items]                        
Debt instrument, basis spread on variable rate       0.50%                
New Credit Agreement | London Interbank Offered Rate (LIBOR)                        
Line of Credit Facility [Line Items]                        
Debt instrument, basis spread on variable rate       1.00%                
New Credit Agreement | London Interbank Offered Rate (LIBOR) | Minimum                        
Line of Credit Facility [Line Items]                        
Debt instrument applicable margin rate       1.25%                
New Credit Agreement | London Interbank Offered Rate (LIBOR) | Maximum                        
Line of Credit Facility [Line Items]                        
Debt instrument applicable margin rate       2.25%                
New Credit Agreement | Base Rate | Minimum                        
Line of Credit Facility [Line Items]                        
Debt instrument applicable margin rate       0.25%                
New Credit Agreement | Base Rate | Maximum                        
Line of Credit Facility [Line Items]                        
Debt instrument applicable margin rate       1.25%                
New Credit Agreement | Revolving Credit Facility                        
Line of Credit Facility [Line Items]                        
Maximum borrowing capacity   $ 100,000,000                    
Swingline sublimit   $ 10,000,000                    
New Credit Agreement | Revolving Credit Facility | Minimum                        
Line of Credit Facility [Line Items]                        
Commitment fee (as a percent)   0.15%                    
New Credit Agreement | Revolving Credit Facility | Maximum                        
Line of Credit Facility [Line Items]                        
Commitment fee (as a percent)   0.35%                    
New Credit Agreement | Term Loan                        
Line of Credit Facility [Line Items]                        
Maximum borrowing capacity   $ 100,000,000                    
Current outstanding borrowings         5,000,000              
Long-term outstanding borrowings         $ 91,800,000              
New Credit Agreement | Delayed Draw Term Loan                        
Line of Credit Facility [Line Items]                        
Maximum borrowing capacity   $ 50,000,000