Stock-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2012

Summary of Restricted Stock Unit Activity

The table below summarizes restricted stock unit activity for the year ended December 31, 2012:

	Restricted Stock Units			Weighted Average Grant Date Fair Value
Restricted stock units outstanding at December 31, 2011		806,263		$	28.31
Granted		287,604			42.50
Released		(132,846	)		26.40
Cancelled		(28,420	)		30.15
Restricted stock units outstanding at December 31, 2012		932,601			32.90