Stockholders' Equity (Tables)

9 Months Ended

Sep. 30, 2020

Stockholders' Equity Note [Abstract]

Schedule of Stock Option and Restricted Stock Activity

Stock option and restricted stock activity for the Plans was as follows for the nine months ended September 30, 2020:

		Options outstanding						Restricted stock outstanding
	Number of shares available for issuance under the Plans	Number of shares outstanding under the Plans	Weighted- average exercise price per share		Weighted- average remaining contractual term (In years)	Aggregate intrinsic value		Number of shares outstanding under the Plans	Weighted- average grant date fair value per share
Balance at December 31, 2019	66.2	2.0	$	12.28	6.5	$	16.40	30.7	$	20.48
Additional shares authorized	21.7	—	—		—	—		—	—
Options exercised and restricted stock units and awards released	—	(0.4)	4.74		—	—		(9.4)	19.75
Options and restricted stock units and awards canceled	7.8	(0.2)	17.52		—	—		(7.6)	20.14
Shares repurchased for tax withholdings on release of restricted stock units and awards	3.3	—	—		—	—		—	19.74
Options and restricted stock units and awards granted	(22.5)	—	—		—	—		22.5	18.85
Balance at September 30, 2020	76.5	1.4	$	13.55	5.9	$	10.29	36.2	$	19.73
Vested at September 30, 2020		1.0	$	16.19	5.3	$	5.57	—	$	—
Unvested at September 30, 2020		0.4	$	5.69		$	4.72	36.2	$	19.73

Schedule of Pre-Tax Intrinsic Value

The following table summarizes information about the pre-tax intrinsic value of options exercised during the three and nine months ended September 30, 2020 and 2019:

	Three Months Ended September 30,				Nine Months Ended September 30,
	2020		2019		2020		2019
Intrinsic value of options exercised	$	0.5	$	0.3	$	5.3	$	4.8

Fair Value of Stock Options Assumptions Used

The fair value of stock options assumed were estimated using the following assumptions:

Expected volatility	51.6	%
Expected term (in years)	3.4 - 7.0
Risk-free interest rate	2.42% - 2.51%
Dividend yield	—	%