Share-Based Compensation Schedule of Grants Subsequent to December 31, 2012 (Details) (USD $)	Feb. 25, 2013
Cumulative Vesting Date May 1, 2015 | Performance-based restricted stock shares
Subsequent Events
Vesting Percentage	33.00%
Cumulative Vesting Date May 1, 2015 | Service-based restricted stock shares
Subsequent Events
Vesting Percentage	33.00%
Cumulative Vesting Date May 1, 2016 | Performance-based restricted stock shares
Subsequent Events
Vesting Percentage	66.00%
Cumulative Vesting Date May 1, 2016 | Service-based restricted stock shares
Subsequent Events
Vesting Percentage	66.00%
Cumulative Vesting Date May 1, 2017 | Performance-based restricted stock shares
Subsequent Events
Vesting Percentage	100.00%
Cumulative Vesting Date May 1, 2017 | Service-based restricted stock shares
Subsequent Events
Vesting Percentage	100.00%
Forfeited | Performance-based restricted stock shares
Subsequent Events
Forfeited	40,440
Granted
Subsequent Events
Granted	59,430
Grant Date Fair Value	7.60
Granted | Performance-based restricted stock shares
Subsequent Events
Granted	28,748
Granted | Service-based restricted stock shares
Subsequent Events
Granted	30,682