Stockholders' Equity and Equity Compensation Plans (Tables)

6 Months Ended

Jun. 30, 2016

Stockholders Equity Note [Abstract]

Summary of Unvested Restricted Common Stock Activity

Stock-Based Awards. A summary of our unvested restricted common stock activity during the second quarter is as follows (shares in thousands):

	Quarter Ended					Six Months Ended
	June 30, 2016					June 30, 2016
	Shares			Weighted- Average Grant Date Fair Value		Shares			Weighted- Average Grant Date Fair Value
Unvested awards, beginning		1,794		$	30.35		2,124		$	26.03
Awards granted		23			42.72		484			38.78
Awards forfeited/cancelled		(45	)		29.67		(163	)		28.61
Awards vested		(28	)		31.23		(701	)		23.10
Unvested awards, ending		1,744		$	30.51		1,744		$	30.51