XML 102 R61.htm IDEA: XBRL DOCUMENT v3.21.1
Earnings Per Share - Computation of Earnings Per Share (Parenthetical) (Detail) - shares
shares in Millions
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Excluded Common Shares issuable under Company's Incentive Stock Option Plan 4.7 4.0