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Employee Benefit Plans - Additional Information (Details) | 12 Months Ended |  |  |
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Dec. 31, 2018 USD ($) Employer Plans Members shares | Dec. 31, 2017 USD ($) | Dec. 31, 2016 USD ($) | Jun. 30, 2017 shares | Jun. 30, 2015 shares | Jun. 30, 2012 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Number of active stock compensation plans | Plans | 3 |  |  |  |  |
Restricted stock shares | shares | 704,000 |  |  |  |  |
Number of employers obligated to make contribution under multiemployer plan | Employer | 199 |  |  |  |  |
Number of employee increase / (decrease) under multiemployer benefit percentage | (1.00%) | 0.50% |  |  |  |
Total contributions of multi employer Plan |  | 5.00% |  |  |  |
SERP |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Members of senior management | Members | 12 |  |  |  |  |
Options | Selling, general and administrative expenses |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Compensation expense | $ | $ 0 | $ 0 | $ 0 |  |  |
Restricted stock units and restricted stock awards |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Tax benefit recognized | $ | 3,000,000.0 | 4,200,000 | 4,200,000 |  |  |
Restricted stock units and restricted stock awards | Selling, general and administrative expenses |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Compensation expense | $ | 11,900,000 | 11,100,000 | 11,200,000 |  |  |
Restricted stock units and restricted stock awards |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Compensation expense not yet recognized | $ | $ 32,700,000 |  |  |  |  |
Total compensation cost related to non-vested options expected to be recognized over weighted average period | 6 years 10 months 24 days |  |  |  |  |
401(k) plan |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Employer contribution | $ | $ 9,200,000 | $ 8,000,000.0 | $ 8,000,000.0 |  |  |
2012 Formula Plan | Restricted stock awards | Board of Directors |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Restricted stock shares | shares | 40,000 |  |  |  |  |
2012 Formula Plan | Class A common stock |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Number of shares authorized | shares |  |  |  | 500,000 |  | 300,000
2012 Plan | Restricted stock units |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Stock award vesting period | 3 years |  |  |  |  |
2012 Plan | Restricted stock units | Executive officers and other key associates |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Restricted stock shares | shares | 664,000 |  |  |  |  |
2012 Plan | Class A common stock |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Number of shares authorized | shares |  |  |  |  | 4,000,000 | 2,000,000
2012 Formula Plan and 2004 Plan | Class A common stock | Options |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Stock option expiration period | 10 years |  |  |  |  |
2012 Formula Plan and 2004 Plan | Class A common stock | Options | Minimum |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Stock award vesting period | 6 months |  |  |  |  |
2012 Formula Plan and 2004 Plan | Class A common stock | Options | Maximum |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Stock award vesting period | 3 years |  |  |  |  |
2012 Formula Plan and 2004 Plan | Class A common stock | Restricted stock awards and restricted stock units | Minimum |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Stock award vesting period | 1 year |  |  |  |  |
2012 Formula Plan and 2004 Plan | Class A common stock | Restricted stock awards and restricted stock units | Maximum |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Stock award vesting period | 3 years |  |  |  |  |

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