Stock-Based Compensation - Changes in Nonvested Stock Options (Details) (USD $)	12 Months Ended
	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Number of Shares [Roll Forward]
Options, Nonvested, Beginning balance (shares)	456,251
Options, Nonvested, Granted (in shares)	71,000
Options, Nonvested, Vested (shares)	(168,198)
Options, Nonvested, Forfeited (shares)	(35,488)
Options, Nonvested, Ending balance (shares)	323,565
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Options, Nonvested, Weighted Average Grant Date Fair Value, Beginning balance, (in dollars per share)	$ 8.24
Options, Nonvested, Weighted Average Grant Date Fair Value, Granted, (in dollars per share)	$ 12.62
Options, Nonvested, Weighted Average Grant Date Fair Value, Vested, (in dollars per share)	$ 7.87
Options, Nonvested, Weighted Average Grant Date Fair Value, Forfeited, (in dollars per share)	$ 8.14
Options, Nonvested, Weighted Average Grant Date Fair Value, Ending balance, (in dollars per share)	$ 9.42