Earnings Per Share (Tables)

12 Months Ended

Dec. 31, 2013

Earnings Per Share [Abstract]

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

	Years Ended December 31,
	2013	2012	2011
Weighted average common shares outstanding—basic	76,821	75,498	75,333
Dilutive effect of potential common shares	567	149	17
Weighted average common shares outstanding—diluted	77,388	75,647	75,350