Quarterly Results of Operations (Unaudited) (Details) - USD ($) $ / shares in Units, $ in Thousands |
3 Months Ended | 12 Months Ended | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
Dec. 31, 2020 |
Sep. 30, 2020 |
Jun. 30, 2020 |
Mar. 31, 2020 |
Dec. 31, 2019 |
Sep. 30, 2019 |
Jun. 30, 2019 |
Mar. 31, 2019 |
Dec. 31, 2020 |
Dec. 31, 2019 |
Dec. 31, 2018 |
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| Operating revenue | $ 350,341 | $ 331,997 | $ 281,678 | $ 305,557 | $ 319,656 | $ 313,683 | $ 302,887 | $ 278,961 | $ 1,269,573 | $ 1,215,187 | $ 1,137,613 |
| Net income and comprehensive income from continuing operations | 15,133 | 16,992 | 9,225 | 11,417 | 22,336 | 21,054 | 21,244 | 17,688 | 52,767 | 82,322 | 88,563 |
| Income from operations | 73,924 | 112,416 | 117,216 | ||||||||
| (Loss) income from discontinued operation, net of tax | (19,576) | (345) | (6,071) | (3,042) | 1,832 | 1,141 | 1,086 | 719 | (29,034) | 4,777 | 3,488 |
| Net income from continuing operations | $ (4,443) | $ 16,647 | $ 3,154 | $ 8,375 | $ 24,168 | $ 22,195 | $ 22,330 | $ 18,407 | $ 23,733 | $ 87,099 | $ 92,051 |
| Net income per share: | |||||||||||
| Net income per share | $ (0.17) | $ 0.60 | $ 0.11 | $ 0.30 | $ 0.86 | $ 0.78 | $ 0.78 | $ 0.64 | $ 0.84 | $ 3.06 | $ 3.14 |
| Diluted | (0.17) | 0.60 | 0.11 | 0.30 | 0.85 | 0.78 | 0.78 | 0.64 | 0.84 | 3.04 | 3.12 |
| Continuing operations | 0.55 | 0.61 | 0.33 | 0.41 | 0.79 | 0.74 | 0.74 | 0.61 | 1.90 | 2.89 | 3.02 |
| Discontinued operation | (0.72) | (0.01) | (0.22) | (0.11) | 0.07 | 0.04 | 0.04 | 0.03 | (1.05) | 0.17 | 0.12 |
| Continuing operations | 0.55 | 0.61 | 0.33 | 0.41 | 0.79 | 0.74 | 0.74 | 0.61 | 1.89 | 2.87 | 3.00 |
| Discontinued operation | $ (0.72) | $ (0.01) | $ (0.22) | $ (0.11) | $ 0.07 | $ 0.04 | $ 0.04 | $ 0.03 | $ (1.05) | $ 0.17 | $ 0.12 |
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- Definition Per basic share amount, after tax, of income (loss) from the day-to-day business activities of the discontinued operation. No definition available.
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- Definition Per diluted share amount, after tax, of income (loss) from the day-to-day business activities of the discontinued operation. No definition available.
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- References No definition available.
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- Definition The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount after tax of income (loss) from continuing operations attributable to the parent. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The amount of net income (loss) from continuing operations per each share of common stock or unit outstanding during the reporting period. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The amount of net income (loss) derived from continuing operations during the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount after tax of income (loss) from a discontinued operation attributable to the parent. Includes, but is not limited to, the income (loss) from operations during the phase-out period, gain (loss) on disposal, gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and adjustments to a prior period gain (loss) on disposal. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The portion of profit or loss for the period, net of income taxes, which is attributable to the parent. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The net result for the period of deducting operating expenses from operating revenues. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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