Stock-Based Compensation and Awards - Restricted Stock, Restricted Stock Units, Performance Units, Cash Settled Restricted Stock Units and Cash Settled Performance Units (Narrative) (Details) - Restricted stock, restricted stock units, performance units, cash settled restricted stock units and cash settled performance units $ in Millions |
12 Months Ended |
|---|---|
|
Dec. 31, 2016
USD ($)
| |
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |
| Vesting period | 3 years |
| Unrecognized compensation cost | $ 15.5 |
| Weighted-average vesting period | 1 year 9 months 18 days |
| First anniversary vesting | |
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |
| Vesting percentage | 33.33% |
| Second anniversary vesting | |
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |
| Vesting percentage | 33.33% |
| Third anniversary vesting | |
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |
| Vesting percentage | 33.33% |