Quarterly report pursuant to Section 13 or 15(d)

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

v3.21.2
Stock-Based Compensation Plans - Amendments to Restricted Stock and SARs - Additional Information (Detail) - Deferred stock units [Member]
Nov. 05, 2013
shares
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 shares of deferred stock units settled in the event of death or termination after reaching age 67 100.00%
Share Based Compensation Arrangement By Share Based Payment Award Stock Appreciation Rights Offering Date Mar. 31, 2013
Two Thousand And Thirteen Omnibus Equity Award Plan [Member]  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Fully Vested Deferred Stock Units Remaining Outstanding 281,193