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Debt and Credit Facilities - Additional Information (Details)
 1 Months Ended 3 Months Ended 12 Months Ended
Aug. 31, 2020
USD ($)
d
$ / shares
shares
Mar. 31, 2021
USD ($)
d
$ / shares
shares
Mar. 31, 2020
USD ($)
Dec. 31, 2020
USD ($)
Jan. 01, 2021
USD ($)
Aug. 10, 2020
USD ($)
Jul. 01, 2014
USD ($)
Debt Instrument [Line Items]              
Letters of credit outstanding amount   $ 203,900,000   $ 193,100,000      
Deferred tax liabilities   13,146,000   12,285,000      
Deferred tax assets   143,022,000   130,200,000      
Level 2              
Debt Instrument [Line Items]              
Senior notes, fair value   270,500,000          
Senior Notes              
Debt Instrument [Line Items]              
Debt instrument, outstanding amount   200,000,000   200,000,000      
Convertible Senior Notes              
Debt Instrument [Line Items]              
Interest rate 0.25%            
Interest expense   $ 600,000   4,400,000      
Debt amount $ 400,000,000.0            
Exercise of option by initial purchasers aggregate principal amount 50,000,000.0            
Proceeds from issuance and sale of debt 389,700,000            
Transaction fees and other third-party offering expenses $ 10,300,000            
Debt instrument, payment terms   The Convertible Senior Notes accrue interest at a rate of 0.25% per annum, payable semi-annually on February 15 and August 15 of each year beginning on February 15, 2021          
Debt instrument, frequency of periodic payment   semi-annually          
Maturity Date Aug. 15, 2025            
Convertible note converted each amount   $ 1,000          
Convertible notes converted each into shares of common stock | shares   22.2913          
Debt Instrument, conversion price | $ / shares   $ 44.86          
Threshold trading days | d 20 51          
Threshold consecutive trading days | d 30            
Conversion percentage of stock price trigger 130.00%            
Number of business day period 5 days            
Consecutive trading day period 5 days            
Convertible principal amount $ 1,000            
Measurement period, percentage 98.00%            
Percentage of principal amount to redeem convertible senior notes 100.00%            
Percentage of convertible senior notes repurchased at cash 100.00%            
Debt liability $ 336,100,000            
Debt instrument convertible notes additional paid in capital $ 53,600,000            
Convertible senior notes effective interest rate 3.25%            
Net carrying value of notes   $ 400,000,000.0   340,600,000      
Bond hedge term   5 years          
Number of shares issuable upon conversion | shares 8,900,000            
Cost of convertible note hedge transaction $ 55,000,000.0            
Number of common stock acquired by offsetting sale warrants. | shares   8,900,000          
Exercise price of warrants | $ / shares   $ 66.46          
Cash proceeds from sales of warrants   $ 13,800,000          
Convertible Senior Notes | ASU 2020-06              
Debt Instrument [Line Items]              
Reclassification of equity component of convertible senior notes to liabilities   55,000,000.0          
Reclassification of equity component of debt issuance costs to liabilities   1,400,000          
Carrying amount of convertible senior notes adjusted in retained earnings         $ 3,700,000    
Convertible Note Hedge And Warrant Transaction              
Debt Instrument [Line Items]              
Purchase of bond hedges and sale of warrants $ 41,200,000            
Deferred tax liabilities   16,200,000          
Deferred tax assets   16,500,000          
Convertible Note Hedge And Warrant Transaction | ASU 2020-06              
Debt Instrument [Line Items]              
Deferred tax liability reversed   13,900,000          
Additional deferred tax liability related to capitalized debt issuance costs   400,000          
Adjustment to deferred tax asset through retained earnings   900,000          
Private Placement              
Debt Instrument [Line Items]              
Debt issuance costs incurred           $ 500,000 $ 1,100,000
Debt amount             $ 250,000,000.0
Private Placement | Accrued Expenses and Other Current Liabilities              
Debt Instrument [Line Items]              
Interest payable   2,400,000   $ 2,600,000      
Private Placement | Senior Notes              
Debt Instrument [Line Items]              
Interest expense   3,200,000 $ 3,200,000        
Interest payments   $ 6,200,000 6,200,000        
Minimum | Convertible Senior Notes              
Debt Instrument [Line Items]              
Debt Instrument, conversion price | $ / shares $ 44.86            
Percentage of bond hedge and warrant transactions increased conversion price 35.00%            
Maximum | Convertible Senior Notes              
Debt Instrument [Line Items]              
Debt Instrument, conversion price | $ / shares $ 66.46            
Percentage of bond hedge and warrant transactions increased conversion price 100.00%            
Revolving Credit Facility              
Debt Instrument [Line Items]              
Amended and restated credit agreement date   Nov. 30, 2017          
Debt issuance costs incurred   $ 2,000,000.0          
Revolving credit facility   500,000,000          
Increase in revolving credit facility   $ 550,000,000          
Credit agreement extended date   Nov. 30, 2022          
Interest rate   1.86%   1.87%      
Letters of credit outstanding amount   $ 45,300,000   $ 44,900,000      
Interest expense   100,000 $ 300,000        
Debt instrument, outstanding amount   $ 0          
Revolving Credit Facility | Base Rate | Minimum              
Debt Instrument [Line Items]              
Margin interest rate   0.125%          
Revolving Credit Facility | Base Rate | Maximum              
Debt Instrument [Line Items]              
Margin interest rate   1.00%          
Revolving Credit Facility | LIBOR | Minimum              
Debt Instrument [Line Items]              
Margin interest rate   1.125%          
Revolving Credit Facility | LIBOR | Maximum              
Debt Instrument [Line Items]              
Margin interest rate   2.00%