Stock-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2014

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Summarizes Information Related to Restricted Stock

The following table summarizes information related to restricted stock held by the Company’s employees and directors for the periods presented:

	Shares		Weighted Average Grant Date Fair Value per Share
Non-vested shares outstanding December 31, 2013	990,472		$	28.20
Granted	985,685		42.55
Vested	(408,541	)	33.70
Forfeited	(197,198	)	38.89
Non-vested shares outstanding December 31, 2014	1,370,418		$	40.03

Summarizes Information Related to Performance Share Units

The following table summarizes information related to PSUs held by the Company’s officers for the periods presented:

	Initial Unit Awards		Weighted Average Grant Date Fair Value per Unit
Non-vested PSUs at December 31, 2013	269,300		$	33.64
Granted	158,970		41.71
Vested	—		—
Forfeited	(26,130	)	35.86
Non-vested PSUs at December 31, 2014	402,140		$	36.68

Summary of Assumptions

The following assumptions were used for the Monte Carlo model to determine the grant date fair value and associated stock-based compensation expense of the PSUs granted during the periods presented:

	2014 PSUs		2013 PSUs		2012 PSUs
Forecast period (years)	4.00		4.00		4.01
Risk-free interest rate	1.12	%	0.65	%	0.46	%
Oasis stock price volatility	44.49	%	47.48	%	51.00	%