Retirement and Long-Term Incentive Plans - Summary of Status of Restricted Stock Awards (Details) - $ / shares |
12 Months Ended | ||
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Dec. 31, 2020 |
Dec. 31, 2019 |
Dec. 31, 2018 |
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| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||
| Document Fiscal Year Focus | 2020 | ||
| Restricted Stock | |||
| Number of Shares | |||
| Restricted shares at the beginning of period (in shares) | 286,148 | 526,438 | 445,126 |
| Granted (in shares) | 470,004 | 170,936 | 440,185 |
| Vested (in shares) | (113,988) | (255,449) | (250,219) |
| Forfeited (in shares) | (26,520) | (155,777) | (108,654) |
| Restricted shares at the end of period (in shares) | 615,644 | 286,148 | 526,438 |
| Weighted- Average Grant-Date Fair Value Per Share | |||
| Restricted shares at the beginning of period (USD per share) | $ 8.30 | $ 11.56 | $ 12.83 |
| Granted (USD per share) | 3.80 | 6.09 | 11.16 |
| Vested (USD per share) | 8.89 | 11.41 | 10.93 |
| Forfeited (USD per share) | 12.14 | 11.81 | 12.01 |
| Restricted shares at the end of period (USD per share) | $ 4.61 | $ 8.30 | $ 11.56 |
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- Definition This is focus fiscal year of the document report in YYYY format. For a 2006 annual report, which may also provide financial information from prior periods, fiscal 2006 should be given as the fiscal year focus. Example: 2006. No definition available.
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- Definition The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
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- Definition Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
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- Definition The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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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- Details
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