Employee Benefit Plans - Weighted Average Assumptions Used to Determine Benefit Obligation and Net Periodic Benefit Costs (Detail) |
12 Months Ended | |
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Dec. 31, 2017 |
Dec. 31, 2016 |
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| Compensation And Retirement Disclosure [Abstract] | ||
| Discount rate | 3.50% | 4.04% |
| Rate of compensation increase | 3.00% | 3.00% |
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- References No definition available.
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- Definition Weighted average rate increase of compensation, used to determine benefit obligation of defined benefit plan. Plan includes, but is not limited to, pay-related defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Weighted average rate for present value of future retirement benefits cash flows, used to determine net periodic benefit cost of defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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