Earnings Per Share (Computation of Basic and Diluted) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Numerator:
Income from continuing operations	$ 20,388	$ 13,572	$ 45,870	$ 26,132
Denominator:
Denominator for basic earnings per share - Weighted-average shares (shares)	18,258,709	17,244,831	18,122,599	17,141,672
Effect of dilutive stock options (shares)	475,000	618,000	534,000	570,000
Denominator for diluted earnings per share - Adjusted weighted-average shares and assumed conversions (shares)	18,733,777	17,863,035	18,657,258	17,711,972
Basic income from continuing operations per share (in dollars per share)	$ 1.12	$ 0.79	$ 2.53	$ 1.52
Diluted income from continuing operations per share (in dollars per share)	$ 1.09	$ 0.76	$ 2.46	$ 1.48