UNAUDITED QUARTERLY DATA (Details) - USD ($) $ / shares in Units, $ in Thousands |
3 Months Ended | 12 Months Ended | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
Dec. 31, 2018 |
Sep. 30, 2018 |
Jun. 30, 2018 |
Mar. 31, 2018 |
Dec. 31, 2017 |
Sep. 30, 2017 |
Jun. 30, 2017 |
Mar. 31, 2017 |
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
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| UNAUDITED QUARTERLY DATA | |||||||||||
| Revenues | $ 444,623 | $ 487,739 | $ 480,461 | $ 408,742 | $ 414,713 | $ 450,442 | $ 433,555 | $ 375,247 | $ 1,821,565 | $ 1,673,957 | $ 1,573,477 |
| Gross profit (Revenues less cost of services provided) | 223,389 | 251,452 | 249,689 | 202,599 | 207,194 | 231,661 | 229,075 | 186,084 | |||
| Net Income | $ 50,968 | $ 66,628 | $ 65,542 | $ 48,525 | $ 33,735 | $ 51,430 | $ 53,689 | $ 40,270 | $ 231,663 | $ 179,124 | $ 167,369 |
| Income per share: | |||||||||||
| Income per share - Basic (in dollars per share) | $ 0.16 | $ 0.20 | $ 0.20 | $ 0.15 | $ 0.10 | $ 0.16 | $ 0.17 | $ 0.12 | $ 0.71 | $ 0.55 | $ 0.51 |
| Income per share - Diluted (in dollars per share) | $ 0.16 | $ 0.20 | $ 0.20 | $ 0.15 | $ 0.10 | $ 0.16 | $ 0.17 | $ 0.12 | $ 0.71 | $ 0.55 | $ 0.51 |
| X | ||||||||||
- 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 Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount, after deduction of tax, noncontrolling interests, dividends on preferred stock and participating securities; of income (loss) available to common shareholders. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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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- References No definition available.
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