Earnings Per Share (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Numerator:
Net Earnings (Loss)	$ 5,324	$ 5,866
Denominator:
Basic - Average Shares Outstanding (in shares)	18,722,156	18,963,177
Employee stock options (in shares)	506,116	592,859
Diluted - Weighted Average Shares Outstanding (in shares)	19,228,272	19,556,036
Basic Earnings per Share (in dollars per share)	$ 0.28	$ 0.31
Diluted Earnings per Share (in dollars per share)	$ 0.28	$ 0.30
Anti-dilutive securities excluded from earnings per share calculation (in shares)	177,414	83,368