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Employee Benefit Plans - Additional Information (Detail) shares in Millions, $ in Millions | 3 Months Ended
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Mar. 31, 2017 USD ($) shares
Pension Benefits |
Compensation and Retirement Disclosure [Abstract] |
Employer contribution to tax-qualified defined benefit pension plans | $ | $ 80
Minimum |
Compensation and Retirement Disclosure [Abstract] |
Percentage of pre-tax earnings paid for profit sharing plan | 5.00%
Maximum |
Compensation and Retirement Disclosure [Abstract] |
Percentage of pre-tax earnings paid for profit sharing plan | 20.00%
RSUs |
Compensation and Retirement Disclosure [Abstract] |
Share-based compensation, other than options, awards granted | shares | 1.4
Share-based compensation, vesting period | 3 years
Performance Shares |
Compensation and Retirement Disclosure [Abstract] |
Share-based compensation, vesting period | 3 years
Share-Based Compensation, vesting date | Dec. 31, 2019
Number of days used to compute performance period average closing price of restricted stock units | 20 days

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