Basis and Summary of Significant Accounting Policies - Calculation of Dilutive Stock Awards (Details) - shares shares in Thousands |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2019 |
Sep. 30, 2018 |
Sep. 30, 2019 |
Sep. 30, 2018 |
|
| Accounting Policies [Abstract] | ||||
| Weighted Average Shares Outstanding (in shares) | 67,400 | 68,819 | 67,461 | 69,521 |
| Dilutive Effect of Share-Based Awards (in shares) | 1,252 | 1,320 | 1,278 | 1,475 |
| Weighted Average Shares Outstanding Assuming Dilution (in shares) | 68,652 | 70,139 | 68,739 | 70,996 |
| Anti-dilutive securities excluded from the computation of earnings per share assuming dilution (in shares) | 400 | 356 | 455 | 345 |