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Employee Benefit Plans - Summary of Retirement Plan Expense (Detail) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Schedule of Employee Benefit Plans [Line Items] |  |  |
Retirement plan expense | $ 42,937 | $ 56,914 | $ 58,096
Defined benefit pension plans |  |  |
Schedule of Employee Benefit Plans [Line Items] |  |  |
Retirement plan expense | 12,366 | 7,428 | 13,999
Defined contribution retirement plans |  |  |
Schedule of Employee Benefit Plans [Line Items] |  |  |
Retirement plan expense | 35,318 | 38,508 | 37,661
Postretirement benefit plans |  |  |
Schedule of Employee Benefit Plans [Line Items] |  |  |
Retirement plan expense | (2,148) | 963 | 1,343
Deferred compensation and excess benefit plans |  |  |
Schedule of Employee Benefit Plans [Line Items] |  |  |
Retirement plan expense | $ (2,599) | $ 10,015 | $ 5,093

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- Definition Schedule of Employee Benefit Plans [Line Items] + References No definition available. + Details
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- Definition Amount of cost (reversal of cost) for pension and other postretirement benefits. + References No definition available. + Details
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- Details
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- Details
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