Stock-Based Compensation - Restricted and Performance Unit Activity (Details) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract]
Allocated share-based compensation expense	$ 184,000	$ 299,000	$ 289,000	$ 1,000,000
Tax benefit from compensation expense	74,000	1,300,000	115,000	1,200,000
Total compensation cost not yet recognized	1,700,000		1,700,000
Total compensation cost not yet recognized, period for recognition			3 years 0 months 0 days
Retricted and performance unit activity
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Outstanding - beginning of period (in shares)			200,165
Granted (in shares)			29,000
Vested (in shares)			(58,326)
Forfeited (in shares)			(19,888)
Outstanding - end of period (in shares)	150,951		150,951
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]
Outstanding - beginning of period, Weighted-Average Grant Date Fair Value (in dollars per share)			$ 11.57
Granted, Weighted-Average Grant Date Fair Value (in dollars per share)			$ 16.75
Vested, Weighted-Average Grant Date Fair Value (in dollars per share)			$ 10.52
Forfeited, Weighted-Average Grant Date Fair Value (in dollars per share)			$ 11.92
Outstanding - end of period, Weighted-Average Grant Date Fair Value (in dollars per share)	$ 12.99		$ 12.99
Performance shares
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract]
Equity instruments other than options, vested in period			$ 862,000	$ 3,900,000