SHARE-BASED AWARDS (Tables)

9 Months Ended

12 Months Ended

Sep. 30, 2020

Dec. 31, 2019

SHARE-BASED AWARDS

Summary of the stock option activity

A summary of the stock option activity for the nine months ended September 30, 2020, is as follows:

			Weighted-
		Weighted-	Average	Aggregate
	Number of	Average	Remaining	Intrinsic
	Options	Exercise	Contractual	Value
	(in thousands)	Price	Term (in years)	(in thousands)
Balance – December 31, 2019	22,633	3.00	6.9	110,481
Exercised	(378)	2.85
Forfeited	(2,734)	3.67
Expired	(796)	3.65
Balance – September 30, 2020	18,725	2.88	6.0	93,646
Exercisable – September 30, 2020	13,096	2.37	5.3	72,214

A summary of the stock option activity for the year ended December 31, 2019, is as follows:

				Weighted-
		Weighted-		Average	Aggregate
	Number of	Average		Remaining	Intrinsic
	Options	Exercise		Contractual	Value
	(in thousands)	Price		Term (in years)	(in thousands)
Balance – December 31, 2018	26,330	$	2.53	8.7	$	113,031
Granted	3,661		5.56
Exercised	(1,928)		1.83
Forfeited	(5,256)		2.85
Expired	(174)		2.86
Balance – December 31, 2019	22,633		3.00	6.9	$	110,481
Exercisable – December 31, 2019	10,870		2.17	6.0	$	62,060

Summary of the RSU activity

A summary of the RSU activity for the nine months ended September 30, 2020, is as follows:

		Weighted-
	Number of	Average
	RSUs	Grant-Date
	(in thousands)	Fair Value
Unvested and outstanding – December 31, 2019	14,070	$	6.80
Granted	8,592		7.60
Forfeited	(3,000)		6.99
Unvested and outstanding – September 30, 2020	19,662		7.12
Vested and outstanding – September 30, 2020	—		—

A summary of the RSU activity for the year ended December 31, 2019, is as follows:

		Weighted-
	Number of	Average
	RSUs	Grant-Date
	(in thousands)	Fair Value
Unvested and outstanding – December 31, 2018	564	$	4.88
Granted	13,901		6.87
Forfeited	(395)		6.71
Unvested and outstanding – December 31, 2019	14,070	$	6.79
Vested and outstanding – December 31, 2019	—		—

Summary of the Restricted Shares activity

A summary of the Restricted Shares activity for the nine months ended September 30, 2020 is as follows:

		Weighted-
	Number of	Average
	Restricted Shares	Grant-Date
	(Thousands)	Fair Value
Unvested – December 31, 2019	2,156	$	5.98
Vested	(636)	$	5.90
Unvested – September 30, 2020	1,520	$	6.01

A summary of the Restricted Shares activity for the year ended December 31, 2019 is as follows:

	Number of	Average
	Restricted Shares	Grant-Date
	(In thousands)	Fair Value
Unvested – December 31, 2018	1,666	$	4.88
Granted	1,263		6.94
Vested	(773)		5.18
Unvested – December 31, 2019	2,156	$	5.98
Vested and outstanding – December 31, 2019	—		—

Summary of stock-based compensation expense in the statements of operations

We recognized stock-based compensation expense in the statements of operations for the nine months ended September 30, 2020 and 2019, as follows (in thousands):

	Nine months Ended September 30,
	2020	2019
Stock options	5,411	7,085
Excess of the repurchase price over the fair value of common stock awards repurchased	—	590
Vesting of restricted shares	3,751	2,315
Total stock-based compensation expense	9,162	9,990

We recognized stock-based compensation expense in the statements of operations for the years ended December 31, 2019, 2018 and 2017, as follows (in thousands):

	2019		2018		2017
Stock options	$	9,175	$	7,526	$	3,761
Excess of the repurchase price over the fair value of common stock awards repurchased		590		6,552		—
Vesting of restricted shares		3,431		896		—
Total stock-based compensation expense	$	13,196	$	14,974	$	3,761

Summary of assumptions used in the Black-Scholes Model for employee and non-employee stock options

The range of assumptions used in the Black-Scholes Model for options for the nine months ended September 30, 2019 are as follows:

	2019
	Range
Fair value	$	6.82
Volatility		32%
Risk-free rate		1.80% – 2.34%
Expected life (in years)		5 – 7
Expected dividend	$	—

The range of assumptions used in the Black-Scholes Model for employee and non-employee stock options for 2019, 2018, and 2017 are as follows:

	2019 Range			2018 Range			2017 Range
Fair value		$6.82 – $6.94			$2.29 – $4.88			$1.64 – $2.59
Volatility		32% – 45	%		32% – 34	%		34% – 36	%
Risk-free rate		1.63% – 2.34	%		2.68% – 3.17	%		2.02% – 2.42	%
Expected life (in years)		5 – 7			5 – 7			7
Expected dividend	$	—		$	—		$	—