Quarterly report pursuant to Section 13 or 15(d)

Stock-Based Compensation Plans - Amendments to Restricted Stock and SARs - Additional Information (Detail)

v3.10.0.1
Stock-Based Compensation Plans - Amendments to Restricted Stock and SARs - Additional Information (Detail) - shares
 9 Months Ended
Oct. 30, 2013
Oct. 01, 2013
Sep. 30, 2018
Dec. 31, 2018
Deferred stock units [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Employee termination age 67 years      
DSU settlement to common stock percentage 20.00%      
DSU settlement into actual stock issued term 5 years      
Percentage of shares of deferred stock units settled in the event of death or termination after reaching age 67 100.00%      
Restricted Stock Sales Restriction [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Sales restriction lapse percentage for restricted stock 20.00%      
Employee termination age 67 years      
Sales restriction period for restricted stock 5 years      
Percentage of shares of stock released from resale restriction upon consummation of change of control 100.00%      
Percentage of shares of restricted released from resale restriction in the event of death or termination after reaching age 67 100.00%      
Number of original shares subject to resale restriction   3,689,326    
Number of shares remain subject to sales restriction     732,020  
Restricted Stock Sales Restriction [Member] | Scenario, Forecast [member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Number of shares remain subject to sales restriction to be released       732,020