Stock-Based Compensation Plans - Schedule of Future Share Settlements (Detail) - 2013 Omnibus Equity Incentive Plan [Member] - Deferred stock units [Member] - shares |
12 Months Ended | |
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Dec. 31, 2017 |
Dec. 31, 2016 |
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| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||
| 2018 | 237,052 | |
| 2021 | 60,373 | |
| 2022 | 281,193 | |
| Total | 578,618 | 930,419 |
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- Definition Fully vested deferred stock units remaining outstanding. No definition available.
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- Definition Fully Vested Deferred Stock Units Reserved For Future Issuance In Next Twelve Months No definition available.
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- Definition Fully vested deferred stock units reserved for future issuance in year five. No definition available.
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- Definition Fully Vested Deferred Stock Units Reserved For Future Issuance In Year Four No definition available.
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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