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Stock-Based Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, shares in Millions, $ in Millions |  | 1 Months Ended | 3 Months Ended | 9 Months Ended |
--- | --- | --- | --- | --- | ---
Jul. 17, 2019 | Jan. 31, 2019 | Jan. 31, 2018 | Sep. 29, 2019 | Sep. 29, 2019 | Sep. 30, 2018 | Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award |  |  |  |  |  |  |
Minimum age of retirement to be eligible for PRSUs |  |  |  |  | 60 years |  |
Estimated annual dividend amount per share |  |  |  |  | $ 0.36 | $ 0.36 |
Stock Based Compensation Relating To Retirement Agreement |  |  |  | $ 2.1 | $ 2.1 |  |
CEO Gregory Beecher [Member] |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award |  |  |  |  |  |  |
Date Of Retirement | Jul. 17, 2019 |  |  |  |  |  |
Stock Options |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award |  |  |  |  |  |  |
Period of stock granted to employees and executive officers vest in equal annual installments |  |  |  |  | 4 years |  |
Percentage of common stock price paid |  |  |  |  | 100.00% |  |
Stock options term |  |  |  |  | 7 years |  |
Restricted Stock Units | Employees |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award |  |  |  |  |  |  |
Period of stock granted to employees and executive officers vest in equal annual installments |  |  |  |  | 4 years |  |
Restricted Stock Units | Director |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award |  |  |  |  |  |  |
Period of stock granted to employees and executive officers vest in equal annual installments |  |  |  |  | 1 year |  |
Percentage of awards vesting on the first anniversary of grant date |  |  |  |  | 100.00% |  |
TSR Performance-Based Restricted Stock Units |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award |  |  |  |  |  |  |
Total shareholder return performance measurement period |  |  | 3 years |  |  |  |
Minimum years of service for retirement to be eligible for PRSUs |  |  |  |  | 10 years |  |
Restricted stock unit awards granted |  |  |  |  | 0.1 | 0.1 |
Weighted average grant date fair value of restricted stock units granted |  |  |  |  | $ 51.51 | $ 54.85 |
Stock price |  | $ 37.95 |  |  |  |  | $ 47.70
TSR Performance-Based Restricted Stock Units | Measurement Input, Expected Dividend Payment [Member] |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award |  |  |  |  |  |  |
Estimated annual dividend amount per share |  |  |  |  | $ 0.36 | $ 0.36 |
TSR Performance-Based Restricted Stock Units | Share-based Compensation Award, Tranche One |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award |  |  |  |  |  |  |
Percentage of vesting of target shares upon performance achieved |  | 200.00% |  |  |  |  |
TSR Performance-Based Restricted Stock Units | Share-based Compensation Award, Tranche Two |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award |  |  |  |  |  |  |
Percentage of vesting of target shares upon performance achieved |  | 0.00% |  |  |  |  |
PBIT Performance-Based Restricted Stock Units |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award |  |  |  |  |  |  |
Total shareholder return performance measurement period |  | 3 years |  |  |  |  |
Restricted stock unit awards granted |  |  |  |  | 0.1 | 0.1 |
Weighted average grant date fair value of restricted stock units granted |  |  |  |  | $ 36.88 | $ 46.62 |
PBIT Performance-Based Restricted Stock Units | Share-based Compensation Award, Tranche One |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award |  |  |  |  |  |  |
Percentage of vesting of target shares upon performance achieved |  |  | 200.00% |  |  |  |
PBIT Performance-Based Restricted Stock Units | Share-based Compensation Award, Tranche Two |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award |  |  |  |  |  |  |
Percentage of vesting of target shares upon performance achieved |  |  | 0.00% |  |  |  |
Service-Based Restricted Stock Units | Employees |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award |  |  |  |  |  |  |
Restricted stock unit awards granted |  |  |  |  | 0.7 | 0.6 |
Weighted average grant date fair value of restricted stock units granted |  |  |  |  | $ 36.85 |  |
Weighted average grant date fair value of restricted stock units granted |  |  |  |  |  | $ 46.25 |
Service-Based Restricted Stock Units | Executive Officer |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award |  |  |  |  |  |  |
Restricted stock unit awards granted |  |  |  |  |  | 0.1 |
Weighted average grant date fair value of restricted stock units granted |  |  |  |  |  | $ 12.17 |
Service-Based Restricted Stock Units | Non Employee Directors |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award |  |  |  |  |  |  |
Restricted stock unit awards granted |  |  |  |  | 0.1 | 0.1 |
Weighted average grant date fair value of restricted stock units granted |  |  |  |  | $ 48.03 | $ 35.81 |
Service-Based Restricted Stock Units | CEO Gregory Beecher [Member] |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award |  |  |  |  |  |  |
Description Of Vesting Agreement | unvested time-based restricted stock units and stock options granted prior to 2019 were modified to allow continued vesting; unvested time-based restricted stock units and stock options granted in 2019 were modified to allow continued vesting through January 31, 2023 (the “Non-Competition Period”) in a pro-rated amount based on the number of days that Mr. Beecher was employed during 2019 |  |  |  |  |  |
Service Based Stock Options | Executive Officer |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award |  |  |  |  |  |  |
Weighted average grant date fair value of restricted stock units granted |  |  |  |  | $ 10.61 |  |
Number options granted during the period |  |  |  |  | 0.1 |  |
Performance Shares | CEO Gregory Beecher [Member] |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award |  |  |  |  |  |  |
Description Of Vesting Agreement | unvested, performance-based restricted stock units awarded in 2019 will vest on the date the amount of shares underlying the performance-based restricted stock units are determined in a pro-rated amount of shares based on the number of days that Mr. Beecher was employed during 2019 |  |  |  |  |  |

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