Stock-based Awards

9 Months Ended

Sep. 30, 2017

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

Stock based awards

Stock-based Awards

Stock Options

A summary of the Company’s stock option activity for the nine months ended September 30, 2017 is as follows:

	Number of Options		Weighted-Average Exercise Price		Weighted-Average Remaining Contractual Life
					(in years)
Outstanding at December 31, 2016	24,541,512		$	8.29	5.49
Granted	4,812,839		18.41
Exercised	(11,517,023	)	6.29
Canceled/forfeited	(748,821	)	8.68
Outstanding at September 30, 2017	17,088,507		$	12.48	7.90

At September 30, 2017, total remaining stock-based compensation expense for unvested stock option awards was $60.2 million, which is expected to be recognized over a weighted-average period of 3.2 years. For the three months ended September 30, 2017 and 2016, the Company recorded stock-based compensation expense for stock option awards of $5.3 million and $3.5 million, respectively. For the nine months ended September 30, 2017 and 2016, the Company recorded stock-based compensation expense for stock option awards of $12.3 million and $10.9 million, respectively.

Restricted Stock Units

Activity in connection with restricted stock units is as follows for the nine months ended September 30, 2017:

	Number of Shares		Weighted- Average Grant Date Fair Value
Non-vested — December 31, 2016	4,339,320		$	7.85
Granted	2,054,374		18.34
Vested	(1,217,878	)	9.10
Canceled/forfeited	(328,678	)	8.88
Non-vested — September 30, 2017	4,847,138		$	11.91

At September 30, 2017, total remaining stock-based compensation expense for non-vested restricted stock units is $54.6 million, which is expected to be recognized over a weighted-average period of 3.1 years. The Company recorded $4.6 million and $2.8 million in stock-based compensation expense for restricted stock units for the three months ended September 30, 2017 and 2016, respectively. The Company recorded $10.4 million and $7.1 million in stock-based compensation expense for restricted stock units for the nine months ended September 30, 2017 and 2016, respectively.

Stock-based Compensation Cost

The Company recorded stock-based compensation cost relating to stock options and restricted stock awards in the following categories on the accompanying consolidated statements of comprehensive loss (in thousands):

	Three Months Ended   September 30,				Nine Months Ended   September 30,
	2017		2016		2017		2016
Cost of revenue	$	339	$	256	$	775	$	711
Sales and marketing	3,358		1,655		7,263		4,154
Technology and development	2,598		1,200		5,496		3,025
General and administrative	3,613		3,130		9,127		10,143
Total stock-based compensation expense	9,908		6,241		22,661		18,033
Amount capitalized to internal software use	443		292		993		760
Total stock-based compensation cost	$	10,351	$	6,533	$	23,654	$	18,793