Annual report pursuant to Section 13 and 15(d)

Share-Based Compensation - Summary of Activities Under Share-Based Compensation Plans (Detail)

v3.20.4
Share-Based Compensation - Summary of Activities Under Share-Based Compensation Plans (Detail) - USD ($)
$ / shares in Units, shares in Thousands, $ in Millions
 12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Outstanding and nonvested as of December 31, 2019, Number of Shares [1] 1,833  
Granted, Number of Shares [2] 1,995  
Vested, Number of Shares [3] (566)  
Forfeited, Number of Shares [4] (194)  
Outstanding and nonvested as of December 31, 2020, Shares [1] 3,068 1,833
Number of Shares, Expected to vest as of December 31, 2020 [5] 2,846  
Outstanding and nonvested as of December 31, 2019, Weighted Average Grant Date Fair Value Per Share [1] $ 49.49  
Granted, Weighted Average Grant Date Fair Value Per Share [2] 39.67  
Vested, Weighted Average Grant Date Fair Value Per Share [3] 46.53  
Forfeited, Weighted Average Grant Date Fair Value Per Share [4] 43.79  
Outstanding and nonvested as of December 31, 2020, Weighted Average Grant Date Fair Value Per Share [1] 44.01 $ 49.49
Expected to vest as of December 31, 2020, Weighted Average Grant Date Fair Value Per Share [5] $ 43.66  
SARs [Member]    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Number of Awards Outstanding, Beginning Balance [6],[7] 7,001  
Exercised, Number of Awards [8] (3,257)  
Forfeited, Number of Awards (7)  
Number of Awards Outstanding, Ending Balance [6],[7] 3,737 7,001
Number of Awards Exercisable, Ending Balance [7],[9] 3,737  
Number of Awards Vested and expected to vest, Ending Balance 3,737  
Weighted Average Exercise Price Per Award Outstanding, Beginning Balance [6],[7] $ 27.85  
Exercised, Weighted Average Exercise Price Per Award [8] 28.56  
Forfeited, Weighted Average Exercise Price Per Award 29.03  
Weighted Average Exercise Price Per Award Outstanding, Ending Balance [6],[7] 27.23 $ 27.85
Exercisable, Weighted Average Exercise Price Per Award, Ending Balance [7],[9] 27.23  
Weighted Average Exercise Price Per Award, Vested and expected to vest, Ending Balance $ 27.23  
Weighted Average Remaining Contractual Term Outstanding [6],[7] 4 years 7 months 6 days 5 years 4 months 24 days
Exercisable Weighted Average Remaining Contractual Term [7],[9] 4 years 7 months 6 days  
Weighted Average Remaining Contractual Term, Vested and expected to vest 4 years 7 months 6 days  
Aggregate Intrinsic Value Outstanding [6],[7],[10] $ 77.8 $ 138.7
Exercisable, Aggregate Intrinsic Value [7],[9],[10] 77.8  
Aggregate Intrinsic Value, Vested and expected to vest [10] $ 77.8  
[1] Includes 712,596 and 475,430 performance based stock unit awards as of December 31, 2020 and 2019, respectively, which represents the maximum amount that can vest.
[2] Includes 504,908 performance-based stock unit awards.
[3] Includes 228,996 performance-based stock unit awards.
[4] Includes 38,746 performance-based stock unit awards.
[5] Includes 561,280 performance-based stock unit awards.
[6] Includes 1.1 million and 2.9 million performance condition SARs as of December 31, 2020 and 2019, respectively.
[7] Includes less than 0.1 million market condition SARS as of both December 31, 2020 and 2019.
[8] Includes 1.8 million performance condition SARs.
[9] Includes less than 0.1 million market condition and 1.1 million performance condition SARs.
[10] The intrinsic value is the amount by which the current market value of the underlying stock exceeds the exercise price of the stock awards.