Stockholders' Deficit

6 Months Ended

Jun. 30, 2016

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

Stockholders' Deficit

Stockholders' Deficit

Stock-based and other incentive compensation

We offer stock-based compensation in the form of stock options and RSUs. We also offered an ESPP through June 30, 2015, at which point in time the shares allocated to this plan were fully issued and the ESPP terminated in accordance with its terms. See Note 18 (Stock-Based and Other Incentive Compensation) in our 2015 Annual Report on Form 10-K. At our annual meeting of stockholders, held on June 15, 2016 (the "Annual Meeting"), our stockholders approved the adoption of a new ESPP, the terms of which are described in our annual proxy statement, filed on Schedule 14A with the SEC on April 29, 2016. The first offering period under the new ESPP will commence on January 1, 2017.

We may grant certain awards in which the vesting is contingent upon the Company achieving certain performance targets. Upon determining that the performance target is probable, the fair value of the award is recognized over the service period, subject to potential adjustment.

We grant stock options to employees and directors under our stock-based compensation plans with exercise prices that are not less than the fair market value of our common stock on the date of grant, as determined pursuant to the terms of the applicable stock-based compensation plan. The terms of the stock option and RSU awards, including the vesting schedule of such awards, are determined at our discretion subject to the terms of the applicable stock-based compensation plan. Options granted over the last several years have generally become exercisable in fourequal installments beginning on the first anniversary of the date of grant or when certain performance targets are determined to have been met, in each case, with a maximum period to exercise of ten years. RSUs typically vest in four equal installments beginning on the first anniversary of the date of grant or when certain performance targets are determined to have been met. We record compensation cost for all stock options and RSUs based on the fair value at the grant date and in the case of performance-based awards, compensation costs may be adjusted to reflect the likelihood of achieving the performance targets.

Stock Options

For the three and six months ended June 30, 2016, we granted 1.2 million options with a weighted average grant date fair value of approximately $4.81. We had approximately 3.0 million and 0.9 million of options outstanding and options exercisable as of June 30, 2016, respectively.

For the three and six months ended June 30, 2016, we recognized stock-based compensation expense of $0.6 million and $1.3 million, respectively, related to the service period of stock options. For the three and six months ended June 30, 2015, we recognized stock-based compensation expense of $0.5 million and $0.9 million, respectively.

As of June 30, 2016, we had $10.2 million of unrecognized stock-based compensation relating to unvested stock options that will be amortized over a weighted average period of approximately two years.

Restricted Stock Units

A summary of the changes in RSUs outstanding under our stock-based compensation plans during the six months ended June 30, 2016 is presented below:

	Number of Restricted Stock Units		Weighted Average Grant Date Fair Value
Unvested RSUs as of December 31, 2015	5.6		$	13.05
Granted	0.2		8.21
Vested	(0.8	)	12.46
Canceled	(0.4	)	12.56
Unvested RSUs as of March 31, 2016	4.6		$	13.00
Granted	1.4		9.60
Vested	(0.6	)	12.51
Canceled	(0.1	)	13.35
Unvested RSUs as of June 30, 2016	5.3		$	12.16

The weighted average grant date fair value of RSUs granted during the three and six months ended June 30, 2016 was $9.60 and $9.42, respectively. During the three and six months ended June 30, 2016 we recognized stock-based compensation expense of $5.4 million and $11.2 million, respectively, related to the vesting of RSUs. For the three and six months ended June 30, 2015, we recognized stock-based compensation expense of $6.3 million and $11.0 million, respectively, related to the service period of RSUs.

As of June 30, 2016, we had $58.0 million of unrecognized stock-based compensation relating to unvested RSUs that will be amortized over a weighted average period of approximately two years.