Quarterly report pursuant to Section 13 or 15(d)

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

v3.3.0.814
Stock-Based Compensation Plans - Amendments to Restricted Stock and SARs - Additional Information (Detail)
 9 Months Ended
Sep. 30, 2015
Deferred stock units [Member]  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
DSU settlement to common stock percentage 20.00%
DSU settlement into actual stock issued term 5 years
Employee termination age 67 years
Percentage of deferred stock units settled 100.00%
Percentage of shares of deferred stock units released from resale restriction in the event of death or termination after reaching age 67 100.00%
Restricted Stock [Member] | Sales Restricted [Member]  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Sales restriction lapse percentage for restricted stock 20.00%
Sales restriction period for restricted stock 5 years
Employee termination age 67 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%