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Financial Instruments - Additional Information (Detail) - USD ($)
3 Months Ended
Mar. 31, 2022
Mar. 31, 2021
Dec. 31, 2021
Financial Instruments [Line Items]      
Period cash equivalents and short-term investments have been in continuous unrealized gain (loss) position, years, maximum 1 year    
Aggregate maximum payments of repurchases of common stock $ 3,828,000    
Cash and cash equivalents, unrestricted $ 190,443,000   $ 319,982,000
Credit Agreement | Revolving Credit Facility | Wintrust Bank N A      
Financial Instruments [Line Items]      
Revolving credit facility maturity date Sep. 08, 2024    
Revolving credit facility $ 125,000,000.0    
Credit facility borrowings $ 0   0
Credit facility,interest rate 1.00%    
Credit Agreement | Revolving Credit Facility | Wintrust Bank N A | Maximum [Member]      
Financial Instruments [Line Items]      
Aggregate commitment amount $ 50,000,000.0    
Aggregate maximum payments of repurchases of common stock $ 100,000,000.0    
Percentage of aggregate amount of loan commitments 125.00%    
Credit Agreement | Revolving Credit Facility | Wintrust Bank N A | Minimum [Member]      
Financial Instruments [Line Items]      
Credit facility,interest rate 3.00%    
CCKF [Member]      
Financial Instruments [Line Items]      
Percentage of investment in equity affiliate 30.70%    
Non controlling interest $ 3,000,000.0    
Gain (loss) from investment in affiliate (100,000) $ 200,000  
Money Market Funds [Member] | Fair Value, Inputs, Level 1 [Member]      
Financial Instruments [Line Items]      
Total short-term investments (available for sale), Fair value 51,800,000   $ 225,300,000
Certificate Of Deposit Commercial Paper And Treasury Bills [Member] | Level 2 [Member]      
Financial Instruments [Line Items]      
Total short-term investments (available for sale), Fair value $ 63,900,000