Quarterly report pursuant to Section 13 or 15(d)

Quarterly report pursuant to Section 13 or 15(d)

Debt - Narrative (Detail)

v3.20.2
Debt - Narrative (Detail)
3 Months Ended 9 Months Ended 12 Months Ended
May 04, 2020
USD ($)
day
$ / shares
Rate
Jun. 27, 2019
USD ($)
Sep. 30, 2020
USD ($)
$ / shares
Rate
shares
Sep. 30, 2019
USD ($)
shares
Sep. 30, 2020
USD ($)
$ / shares
Rate
shares
Sep. 30, 2019
USD ($)
shares
Dec. 31, 2019
USD ($)
Line of Credit Facility [Line Items]              
Issuance of common stock, net         $ 10,761,000 $ 10,132,000  
Dilutive effect of Convertible Notes (in shares) | shares     5,538,360 0 0 0  
Ownership of convertible notes (as a percent) 25.00%            
Proceeds from issuance of convertible debt, net of issuance costs         $ 194,466,000 $ 0  
Short-term portion of term loan     $ 0   0   $ 5,000,000
Long-term portion of term loan, net     0   0   91,829,000
Debt issuance costs     565,000   565,000    
Loss on extinguishment of debt     $ 0 $ 0 $ 1,400,000 $ 1,018,000 $ 1,400,000
Debt instrument, weighted average interest rates     4.91%   4.91%   4.64%
Convertible Debt              
Line of Credit Facility [Line Items]              
Proceeds from issuance of convertible debt, net of issuance costs $ 96,300,000            
Term Loan Facility              
Line of Credit Facility [Line Items]              
Debt issuance costs     $ 0   $ 0   $ 671,000
1.25% Convertible Senior Notes | Convertible Debt              
Line of Credit Facility [Line Items]              
Stated interest rate (as a percent) | Rate 1.25%   1.25%   1.25%    
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 $ 36.34   $ 36.89   $ 36.89    
Convertible debt, if converted, value in excess of principal $ 3,100,000            
Redemption price of principal (as a percent) 100.00%            
Interest expense, contractual coupon interest     $ 600,000   $ 1,000,000.0    
Interest expense, accretion of debt discount     1,800,000   2,700,000    
Interest expense, amortization of debt issuance costs     25,600   $ 44,700    
Effective interest rate on Convertible Notes (as a percent)         5.50%    
Carrying amount of equity component $ 21,600,000   23,100,000   $ 23,100,000    
Debt issuance costs     $ 565,000   $ 565,000   $ 0
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 variable interest rate         0.50%    
New Credit Agreement | LIBOR              
Line of Credit Facility [Line Items]              
Debt instrument variable interest rate         1.00%    
New Credit Agreement | LIBOR | Minimum              
Line of Credit Facility [Line Items]              
Debt instrument applicable margin         1.25%    
New Credit Agreement | LIBOR | Maximum              
Line of Credit Facility [Line Items]              
Debt instrument applicable margin         2.25%    
New Credit Agreement | Base Rate | Minimum              
Line of Credit Facility [Line Items]              
Debt instrument applicable margin         0.25%    
New Credit Agreement | Base Rate | Maximum              
Line of Credit Facility [Line Items]              
Debt instrument applicable margin         1.25%    
New Credit Agreement | Revolving Credit Facility              
Line of Credit Facility [Line Items]              
Line of credit facility maximum borrowing capacity   $ 100,000,000.0          
Line of credit facility, swingline sublimit   $ 10,000,000.0          
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]              
Line of credit facility maximum borrowing capacity   $ 100,000,000.0          
Annual principal amortization, year one (as a percent)   5.00%          
Annual principal amortization, year two (as a percent)   5.00%          
Annual principal amortization, year three (as a percent)   7.50%          
Annual principal amortization, year four (as a percent)   7.50%          
Annual principal amortization, thereafter (as a percent)   10.00%          
Debt instrument, percentage of net cash proceeds from sales and dispositions subject to certain reinvestment rights     100.00%   100.00%    
Debt instrument, percentage of net cash proceeds from issuances or incurrence of additional debt to be used for mandatory prepayment     100.00%   100.00%    
New Credit Agreement | Delayed Draw Term Loan              
Line of Credit Facility [Line Items]              
Line of credit facility maximum borrowing capacity   $ 50,000,000.0          
Over-Allotment Option              
Line of Credit Facility [Line Items]              
Issuance of common stock, net $ 194,400,000