|
Incentive Award Plan and Stock Option Plan - Narrative (Details) (USD $)
In Millions, except Share data, unless otherwise specified
|
3 Months Ended |
|
Mar. 31, 2015
|
Mar. 31, 2014
|
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
|
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| Number of shares authorized under plan (in shares) |
2,000,000 |
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| General and Administrative Expense |
|
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| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
|
|
| Stock-based compensation expense |
$ 3.8 |
$ 2.5 |
| Non-vested shares of restricted stock |
|
|
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
|
|
| Deferred compensation expense |
4.3 |
|
| Outstanding non vested restricted shares (in shares) |
1,300,000 |
|
| Non-vested shares of restricted stock | Directors Officers And Employees |
|
|
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
|
|
| Grants in period (in shares) |
400,000 |
|
| Performance Shares |
|
|
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
|
|
| Shares of common stock available for issuance (in shares) |
236,826 |
|
| Stock-based compensation expense |
3.5 |
|
| Potential grants in period based on total shareholder return (in shares) |
1,000,000 |
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| Dividend rights accrued |
0.7 |
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| Unamortized stock based compensation expense |
$ 16.2 |
|
| Performance Shares | Minimum |
|
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| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
|
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| Multiplier for shares granted |
0.00% |
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| Performance Shares | Maximum |
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| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
|
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| Multiplier for shares granted |
250.00% |
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