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Long-Term Debt and Financing Arrangements - Additional Information (Detail) - USD ($)
6 Months Ended
Jun. 30, 2017
Jul. 01, 2017
Dec. 31, 2016
Subsequent Event [Member] | Credit Agreement [Member]      
Line Of Credit Facility [Line Items]      
Amount of credit agreement   $ 350,000,000  
Standby Letters of Credit [Member]      
Line Of Credit Facility [Line Items]      
Letters of credit expiration year 2017    
Outstanding letters of credit $ 13,500,000    
Revolving Line of Credit Facility [Member] | Bank Revolving Line of Credit [Member]      
Line Of Credit Facility [Line Items]      
Unused and available borrowings under variable rate bank revolving line of credit $ 36,500,000   $ 38,200,000