Selected Quarterly Financial Data - Schedule of Quarterly Financial Data (Detail) - 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 |
|
| Consolidated Financial Statement Data: | |||||||||||
| Total revenues | $ 250,214 | $ 158,575 | $ 117,400 | $ 190,717 | $ 237,908 | $ 198,220 | $ 209,593 | $ 160,707 | $ 716,906 | $ 806,428 | $ 814,816 |
| Cost of services | 160,672 | 99,707 | 73,743 | 113,757 | 155,196 | 124,147 | 127,847 | 91,688 | 447,879 | 498,878 | 502,883 |
| Operating income | 30,052 | 6,540 | (2,614) | 19,636 | 27,104 | 24,072 | 26,978 | 18,269 | 53,614 | 96,423 | 112,287 |
| Net income | $ 23,622 | $ 6,040 | $ 106 | $ 13,070 | $ 20,721 | $ 19,292 | $ 21,279 | $ 15,638 | $ 42,838 | $ 76,930 | $ 87,257 |
| Earnings per share: | |||||||||||
| Basic | $ 0.59 | $ 0.15 | $ 0 | $ 0.33 | $ 0.53 | $ 0.49 | $ 0.54 | $ 0.40 | $ 1.08 | $ 1.95 | $ 2.23 |
| Diluted | $ 0.59 | $ 0.15 | $ 0 | $ 0.33 | $ 0.52 | $ 0.49 | $ 0.54 | $ 0.40 | $ 1.08 | $ 1.95 | $ 2.22 |
| X | ||||||||||
- Definition Variable commissions, compensation-related costs and other costs related to our revenue-generating activities. No definition available.
|
| X | ||||||||||
- 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
|
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- 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
|
| X | ||||||||||
- 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
|
| X | ||||||||||
- Definition The net result for the period of deducting operating expenses from operating revenues. Reference 1: http://www.xbrl.org/2003/role/exampleRef
|
| X | ||||||||||
- Definition Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|
| X | ||||||||||
- References No definition available.
|