Stock Options (Tables)

3 Months Ended

Mar. 31, 2016

The fair value of stock option awards was estimated using the Black-Scholes option pricing model with the following assumptions and weighted-average fair values:


	Three Months Ended March 31,
	2016			2015
Weighted-average fair value of grant	$	4.53		$	9.12
Risk-free interest rate		1.29	%		1.28	%
Expected volatility		51.30	%		45.46	%
Expected life of options in years		4.90			4.92
Expected dividend yield		—			—

Summary of Stock Option Activity

A summary of stock option activity for the three months ended March 31, 2016 follows (shares in thousands):


Options	Shares			Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Term (years)		Aggregate Intrinsic Value ($ in millions)
Outstanding at December 31, 2015		2,723		$	27.88
Granted		11			10.85
Exercised		—			—
Forfeited and expired		(516	)		38.36

Outstanding at March 31, 2016		2,218			25.36		3.08	$	—

Expected to vest at March 31, 2016		684			25.55		4.52		—

Exercisable at March 31, 2016		1,498			25.32		2.37		—

Summary of Restricted Stock Unit Activity

A summary of restricted stock unit activity for the three months ended March 31, 2016 follows (shares in thousands):


	Restricted Stock Units			Weighted- Average Grant-Date Fair Value
Outstanding at December 31, 2015		469		$	23.57
Granted		1,156			10.06
Vested		(154	)		20.17
Forfeited and expired		(3	)		24.40

Outstanding at March 31, 2016		1,468			13.32