|
Incentive Award Plan and Employee Benefit Plan - Narrative (Details) (USD $)
In Millions, except Share data, unless otherwise specified
|
0 Months Ended |
12 Months Ended |
|
Aug. 01, 2013
|
Dec. 31, 2014
|
Dec. 31, 2013
|
Dec. 31, 2012
|
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
|
|
|
|
| Grants in period (in shares) |
367,914 |
|
|
|
| Shares authorized under plan (in shares) |
|
1,300,000 |
|
|
| Shares of common stock available for issuance (in shares) |
|
2,500,000 |
|
|
| Requisition service period |
|
6 months |
|
|
| General and Administrative Expense [Member] |
|
|
|
|
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
|
|
|
|
| Stock-based compensation expense |
|
11.3 |
$ 8.8 |
$ 5.9 |
| Non-Vested Shares of Restricted Stock [Member] |
|
|
|
|
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
|
|
|
|
| Grants in period (in shares) |
|
372,974 |
363,501 |
|
| Deferred compensation expense |
|
4.0 |
|
|
| Non-Vested Shares of Restricted Stock [Member] | Directors Officers and Employees [Member] |
|
|
|
|
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
|
|
|
|
| Grants in period (in shares) |
|
400,000 |
|
|
| Performance Shares [Member] |
|
|
|
|
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
|
|
|
|
| Shares of common stock available for issuance (in shares) |
|
242,883 |
|
|
| Stock-based compensation expense |
|
3.3 |
|
|
| Aggregate shares that would have released under annual performance award (in shares) |
|
1,100,000 |
|
|
| Accrued dividend rights |
|
0.7 |
0.2 |
|
| Unamortized stock-based compensation expense |
|
12.0 |
$ 15.6 |
|
| Maximum [Member] |
|
|
|
|
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
|
|
|
|
| Employer matching contribution |
|
4.00% |
|
|
| Maximum [Member] | Performance Shares [Member] |
|
|
|
|
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
|
|
|
|
| Percent multiplier for shares granted |
|
250.00% |
|
|
| Minimum [Member] | Performance Shares [Member] |
|
|
|
|
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
|
|
|
|
| Percent multiplier for shares granted |
|
0.00% |
|
|