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Share-Based Compensation - Stock Option Plans (Details) $ / shares in Units, $ in Thousands | 12 Months Ended
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Dec. 31, 2016 USD ($) item $ / shares shares | Dec. 31, 2015 USD ($) $ / shares shares | Dec. 31, 2014 USD ($) $ / shares shares | Dec. 31, 2013 USD ($)
Share-based compensation disclosures |  |  |  |
Share-based compensation expense | $ | $ 32,000 | $ 47,300 | $ 37,200 |
Liability related to awards | $ | $ 116,775 | $ 120,204 |  |
Assumptions used to value grant date fair value |  |  |  |
Risk free interest rate (as a percent) | 1.41% | 1.18% | 0.80% |
Expected volatility (as a percent) | 52.00% | 50.00% | 40.00% |
Closing stock price at grant date (in dollars per share) | $ / shares | $ 8.64 | $ 12.98 | $ 18.19 |
Expected term (in years) | 3 years | 3 years | 2 years 11 months 19 days |
Restricted Stock Award |  |  |  |
Share-based compensation disclosures |  |  |  |
Share-based compensation expense | $ | $ 31,300 | $ 37,000 | $ 35,000 |
Share-based compensation expense related to the closing of the Merger | $ | $ 8,700 |  |  |
Number of types of performance share awards | item | 2 |  |  |
Option to purchase common stock available for grant | 6,800,000 |  |  |
Shares awarded during period | 1,885,000 |  |  |
Options |  |  |  |
Forfeited (in shares) | (277,000) |  |  |
Weighted Average Exercise Price |  |  |  |
Forfeited (in dollars per share) | $ / shares | $ 13.33 |  |  |
Restricted Stock Award | Employees and Director |  |  |  |
Share-based compensation disclosures |  |  |  |
Shares awarded during period | 1,885,440 | 2,546,801 | 1,169,000 |
Aggregate value of restricted stock awards at date of grant | $ | $ 20,500 | $ 34,800 | $ 26,700 |
Fair value of awards vested | $ | $ 13,500 | 18,300 | 28,000 |
Restricted Stock Award | Maximum |  |  |  |
Share-based compensation disclosures |  |  |  |
Vesting period of shares | 5 years |  |  |
Restricted Stock Award | Maximum | Employees and Director |  |  |  |
Share-based compensation disclosures |  |  |  |
Vesting period of shares | 4 years |  |  |
Restricted Stock Based on Performance Conditions |  |  |  |
Share-based compensation disclosures |  |  |  |
Shares awarded during period | 1,285,000 |  |  |
Fair value of awards vested | $ |  | 13,900 | 5,900 | $ 8,000
Restricted Stock Based on Performance Conditions | Executives |  |  |  |
Share-based compensation disclosures |  |  |  |
Vesting period of shares | 3 years |  |  |
Total fair value of option vested during the period | $ | $ 1,500 | $ 6,800 | $ 5,900 |
Shares awarded during period | 1,284,829 | 438,307 | 362,311 |
Liability related to awards | $ | $ 2,500 | $ 2,200 |  |
Restricted Stock Based on Market Conditions |  |  |  |
Share-based compensation disclosures |  |  |  |
Vesting period of shares | 3 years |  |  |
Shares awarded during period | 749,000 | 544,925 | 395,550 |
Aggregate value of restricted stock awards at date of grant | $ | $ 4,200 | $ 4,700 | $ 4,500 |
Stock options | Maximum | Employees and Director |  |  |  |
Share-based compensation disclosures |  |  |  |
Vesting period of shares | 5 years |  |  |
Stock options | Minimum | Employees and Director |  |  |  |
Share-based compensation disclosures |  |  |  |
Vesting period of shares | 3 years |  |  |
Key Officer Director and Managerial Employee Stock Options |  |  |  |
Share-based compensation disclosures |  |  |  |
Option to purchase common stock available for grant | 8,000,000 | 3,300,000 |  |
Exercise period | 10 years |  |  |
Total fair value of option vested during the period | $ | $ 1,900 | $ 1,900 | $ 2,000 |
Assumptions used to value grant date fair value |  |  |  |
Granted (in dollars per share) | $ / shares | $ 3.52 | $ 4.40 | $ 6.76 |
Risk free interest rate (as a percent) | 1.09% | 1.29% | 1.37% |
Dividend yield (as a percent) | 2.21% | 2.05% | 1.21% |
Expected volatility (as a percent) | 45.69% | 50.01% | 51.01% |
Expected term (in years) | 4 years | 4 years | 4 years |
Options |  |  |  |
Options outstanding at the beginning of the period (in shares) | 5,298,000 |  |  |
Granted (in shares) | 100,000 | 158,219 |  |
Exercised (in shares) | (102,000) |  |  |
Forfeited (in shares) | (79,000) |  |  |
Options outstanding at the end of the period (in shares) | 5,217,000 | 5,298,000 |  |
Options exercisable at the end of the period (in shares) | 5,161,000 |  |  |
Weighted Average Exercise Price |  |  |  |
Options outstanding at the beginning of the period (in dollars per share) | $ / shares | $ 12.48 |  |  |
Granted (in dollars per share) | $ / shares | 11.28 |  |  |
Exercised (in dollars per share) | $ / shares | 9.53 |  |  |
Forfeited (in dollars per share) | $ / shares | 9.38 |  |  |
Options outstanding at the end of the period (in dollars per share) | $ / shares | 12.56 | $ 12.48 |  |
Options exercisable at the end of the period (in dollars per share) | $ / shares | $ 12.54 |  |  |
Weighted Average Remaining Contractual Term |  |  |  |
Options outstanding at the end of the period | 3 years 4 months 6 days |  |  |
Options exercisable at the end of the period | 3 years 3 months 18 days |  |  |
Aggregate Intrinsic Value |  |  |  |
Options outstanding at the end of the period (in dollars) | $ | $ 23,996 |  |  |
Options exercisable at the end of the period (in dollars) | $ | $ 23,896 |  |  |
Key Officer Director and Managerial Employee Stock Options | Employees Executives And Directors |  |  |  |
Share-based compensation disclosures |  |  |  |
Vesting period of shares | 4 years | 4 years | 4 years |
Options |  |  |  |
Granted (in shares) | 99,711 |  | 60,662 |

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