Employee Benefit Plans (Tables)

12 Months Ended

Dec. 31, 2012

Employee Benefit Plans [Abstract]

Schedule of Company Contributions to 401(k) Plan [Table Text Block]

	Year Ended
	December 31, 2012		December 31, 2011		December 31, 2010
Contributions to 401(k) Plan	$	4,814	$	4,644	$	4,610