Stock-Based Compensation (Tables)

3 Months Ended

Mar. 31, 2018

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

Summary of stock option activity

The following table summarizes the activity for all stock options under all of the Company’s equity incentive plans for the three months ended March 31, 2018 (shares and aggregate intrinsic value in thousands):

	Number of Options		Weighted Average Exercise Price		Weighted Average Remaining Contractual Life	Aggregate Intrinsic Value
Outstanding at December 31, 2017	16,268		$	5.70	7.41	$	14,832
Granted	1,188		8.05
Exercised	(443	)	4.38
Cancelled / forfeited	(184	)	8.30
Outstanding at March 31, 2018	16,829		$	5.87	7.39	$	53,592
Options vested and exercisable at March 31, 2018	8,964		$	5.55	6.18	$	31,957

Summary of activity for all restricted stock units (RSUs)

The following table summarizes the activity for all restricted stock units (“RSUs”) under all of the Company’s equity incentive plans for the three months ended March 31, 2018 (shares in thousands):

	Number of Awards		Weighted Average Grant Date Fair Value
Unvested balance at December 31, 2017	5,330		$	5.82
Granted	1,452		7.77
Issued	(888	)	6.93
Cancelled / forfeited	(406	)	5.41
Unvested balance at March 31, 2018	5,488		$	6.19

Summary of stock-based compensation expense

The Company recognized stock-based compensation expense, including ESPP expenses, in the consolidated statements of operations as follows (in thousands):

	Three Months Ended March 31,
	2018		2017
Cost of customer agreements and incentives	$	611	$	751
Cost of solar energy systems and product sales	170		114
Sales and marketing	4,150		1,917
Research and development	295		149
General and administration	5,468		2,943
Total	$	10,694	$	5,874