Stockholders' Equity (Tables)

6 Months Ended

Jun. 30, 2018

Stockholders Equity Note [Abstract]

Company's Outstanding Restricted Stock Grants

The following table sets forth the activity of the Company’s outstanding restricted stock grants, including shares of restricted stock awarded as a result of the achievement of performance objectives under outstanding performance shares awards, in the quarter ended June 30, 2018:

	Shares			Weighted-average grant date fair value
Shares unvested January 1, 2018		221,313		$	31.42
Shares granted		145,458			45.60
Shares for which restrictions lapsed		(82,165	)		45.79
Shares unvested June 30, 2018		284,606		$	36.51