Earnings Per Share (Tables)

12 Months Ended

Dec. 31, 2014

Earnings Per Share [Abstract]

Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]

The reconciliations of the denominators of the basic and diluted earnings per share computations are as follows (in thousands):

	Years Ended December 31,
	2014	2013	2012
Weighted average common shares outstanding—basic	78,180	76,821	75,498
Dilutive effect of potential common shares	2,314	567	149
Weighted average common shares outstanding—diluted	80,494	77,388	75,647