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Capital Management	12 Months Ended
	Dec. 31, 2017
Text Block [Abstract]
Capital Management	20. Capital Management The Company’s Board of Directors initiated a share repurchase program in February 2010. In October 2016, the Board reauthorized this program with a limit of $25.0 million with no expiration date. There were no shares repurchased under this program in 2017. Since the beginning of this plan, the Company has repurchased a total of 1,258,250 shares for $22.4 million, or an average price of $17.78, including commissions. In 2013, the Company’s Board of Directors initiated a regular quarterly dividend.  During 2017, the Company’s Board of Directors declared a quarterly dividend of $0.20 per share compared to $0.18 per share in 2016, $0.15 per share in 2015, $0.12 per share in 2014 and $0.08 per share in 2013.  The Company declared extraordinary dividends totaling $3.50 per share in 2017, $3.25 per share in 2016, $3.00 per share in 2015 and $1.50 per share in 2014.  The Company did not pay any extraordinary cash dividends in 2013.

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