Stock-Based Compensation (Summary of Non-Vested Restricted Stock Activity) (Details) (USD $)
12 Months Ended
Dec. 31, 2013
Dec. 31, 2012
Dec. 31, 2011
Stock-based Compensation Arrangements, Restricted Stock, Nonvested [Roll Forward]      
Shares Outstanding, Beginning of Period 523,967 790,484 954,029
Shares, Granted 163,417 92,689 293,120
Shares, Vested 160,738 327,707 419,704
Shares, Forfeited 32,184 31,499 36,961
Shares Outstanding, End of Period 494,462 523,967 790,484
Weighted Average Grant-Date Fair Value, Outstanding at Beginning of Period $ 11.94 $ 9.96 $ 7.9
Weighted Average Grant-Date Fair Value, Granted $ 20.29 $ 14.69 $ 11.13
Weighted Average Grant-Date Fair Value, Vested $ 11.05 $ 8.08 $ 5.93
Weighted Average Grant-Date Fair Value, Forfeited $ 16.83 $ 10.49 $ 11.81
Weighted Average Grant-Date Fair Value, Outstanding at End of Period $ 14.67 $ 11.94 $ 9.96