| Fiscal period | 2024 | 2023 | 2022 | 2021 | 2020 | 2019 | 2018 | 2017 | 2016 | 2015 |
|---|
| Period End Date | 12/31/2024 | 12/31/2023 | 12/31/2022 | 12/31/2021 | 12/31/2020 | 12/31/2019 | 12/31/2018 | 12/31/2017 | 12/31/2016 | 12/31/2015 |
|---|
| Revenues | 3,698.65 | 3,489.24 | 3,028.91 | 2,776.22 | 2,461.28 | 2,352.72 | 2,027.88 | 1,807.73 | 1,810.39 | 1,779.15 |
| Total Revenues | 3,698.65 | 3,489.24 | 3,028.91 | 2,776.22 | 2,461.28 | 2,352.72 | 2,027.88 | 1,807.73 | 1,810.39 | 1,779.15 |
| Direct cost of revenues | 2,516.73 | 2,354.22 | 2,065.98 | 1,915.51 | 1,672.71 | 1,534.90 | 1,328.07 | 1,215.56 | 1,210.77 | 1,171.44 |
| Gross Profit | 1,181.93 | 1,135.03 | -- | 860.72 | 788.56 | -- | -- | -- | -- | -- |
| Amortization of goodwill | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- |
| Amortization of other intangible assets | 4.18 | 6.16 | 9.64 | 10.82 | 10.39 | 8.15 | 8.16 | 10.56 | 10.31 | 11.73 |
| Selling, general and administrative expense | 822.15 | 751.31 | 641.07 | 537.84 | 488.41 | 504.07 | 465.64 | 429.72 | 434.55 | 432.67 |
| Acquisition-related contingent consideration | -- | -- | -- | -- | -- | -- | -- | 2.29 | 2.16 | (1.20) |
| Loss on abandoned facilities | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- |
| Special charges | (8.23) | -- | (8.34) | -- | (7.10) | -- | -- | (40.89) | (10.45) | -- |
| Special termination charges | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- |
| Total Operating Expenses | 3,351.29 | 3,111.68 | 2,725.03 | 2,464.17 | 2,178.61 | 2,047.12 | 1,801.87 | 1,699.02 | 1,668.24 | 1,614.64 |
| Operating Income (Loss) | 347.36 | 377.56 | 303.88 | 312.05 | 282.66 | 305.60 | 226.01 | 108.71 | 142.16 | 164.51 |
| Interest expense | 6.95 | 14.33 | 10.05 | 20.29 | 19.81 | 19.21 | 27.15 | 25.36 | 24.82 | 42.77 |
| Interest expense and other | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- |
| Litigation settlement losses (gains), net | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- |
| Interest income | -- | -- | 3.92 | -- | -- | -- | 4.98 | -- | -- | -- |
| Interest income and other | 10.36 | (4.87) | -- | 6.19 | (0.41) | 2.06 | -- | 3.75 | 10.47 | 3.23 |
| Gain on sale of business | -- | -- | -- | -- | -- | -- | 13.03 | -- | -- | -- |
| Loss on early extinguishment of term loans | -- | -- | -- | -- | -- | -- | (9.07) | -- | -- | (19.59) |
| Discount on note receivable | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- |
| Other income (expense), total | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- |
| Total Other income (expense) | 3.41 | (19.20) | (6.13) | (14.10) | (20.22) | (17.15) | (18.21) | (21.61) | -- | (59.13) |
| Income before income tax provision | 350.77 | 358.36 | 297.75 | 297.95 | 262.45 | 288.45 | 207.79 | 87.11 | 127.80 | 105.39 |
| Current-State | -- | -- | -- | -- | -- | -- | -- | 0.74 | 1.69 | -- |
| Current- Foreign | -- | -- | -- | -- | -- | -- | -- | 14.82 | 13.86 | -- |
| Deferred- Foreign | -- | -- | -- | -- | -- | -- | -- | (3.61) | (1.41) | -- |
| Deferred:Federal | -- | -- | (2.72) | -- | -- | -- | -- | (47.82) | 23.18 | -- |
| Deferred:State | -- | -- | (1.17) | -- | -- | -- | -- | (0.15) | 8.28 | -- |
| Income tax (benefit) provision | 70.68 | 83.47 | 62.24 | 62.98 | 51.76 | 71.72 | 57.18 | (20.86) | 42.28 | 39.33 |
| Current-Federal | -- | -- | -- | -- | -- | -- | -- | 15.16 | (3.33) | -- |
| Income from Continuing Operations | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- |
| Discontinued operations:Income taxes | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- |
| Income (loss) from operations of discontinued operations, net of income tax provision | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- |
| Income (loss) from sale of discontinued operations, net of income tax provision | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- |
| Income before extraordinary item | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- |
| Net Income (loss) Available to Common Shareholders | 280.09 | 274.89 | 235.51 | 234.97 | 210.68 | 216.73 | 150.61 | 107.96 | 85.52 | 66.05 |
| Continuing Operations- (Basic) | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- |
| EPS (Basic) : Income (loss) from Discontinued operations | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- |
| Extraordinary item, per common share | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- |
| Earnings per common share (Basic) | 7.96 | 8.10 | 6.99 | 7.02 | 5.92 | 5.89 | 4.06 | 2.79 | 2.09 | 1.62 |
| Continuing Operations- (Diluted) | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- |
| EPS (Diluted) : Income (loss) from Discontinued operations | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- |
| Extraordinary item, per common share | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- |
| Earnings per common share - Diluted | 7.81 | 7.71 | 6.58 | 6.65 | 5.67 | 5.69 | 3.93 | 2.75 | 2.05 | 1.58 |
| Weighted Average Shares Outstanding (Basic) | 35.21 | 33.92 | 33.69 | 33.49 | 35.60 | 36.77 | 37.10 | 38.70 | 40.94 | 40.85 |
| Weighted Average Shares Outstanding (Diluted) | 35.85 | 35.65 | 35.78 | 35.34 | 37.15 | 38.11 | 38.32 | 39.19 | 41.71 | 41.73 |