Equity Incentive Plans and Stock-Based Compensation (Tables)

6 Months Ended

Jun. 30, 2023

Share-Based Payment Arrangement [Abstract]

A summary of shares available for grant under the Company’s plans is as follows:


			Shares Available for Grant
Total shares available for grant as of December 31, 2022			7,655,769
Increase in shares approved for issuance (1)			5,210,000



Nonvested equity stock and stock units granted (2) (3)			(1,987,388)
Nonvested equity stock and stock units forfeited (2)			529,072
Total shares available for grant as of June 30, 2023			11,407,453

_________________________________________

(1) On April 27, 2023, the Company’s stockholders approved these additional shares to be reserved for issuance under the 2015 Equity Incentive Plan (the “2015 Plan”).

(2) For purposes of determining the number of shares available for grant under the 2015 Plan against the maximum number of shares authorized, each restricted stock unit granted prior to April 27, 2023 reduces the number of shares available for grant by 1.5 shares and each restricted stock unit forfeited increases shares available for grant by 1.5 shares. Each restricted stock unit granted on or after April 27, 2023 reduces the number of shares available for grant by 1.0 shares and each restricted stock unit forfeited increases shares available for grant by 1.0 shares.

(3) Amount includes approximately 0.2 million shares that have been reserved for potential future issuance related to certain performance unit awards granted in the first quarter of 2023 and discussed under the section titled “Nonvested Equity Stock and Stock Units” below.

Schedule of stock option activity

The following table summarizes stock option activity under the Company’s equity incentive plans for the six months ended June 30, 2023 and information regarding stock options outstanding, exercisable, and vested and expected to vest as of June 30, 2023.


	Options Outstanding
(In thousands, except shares, per share amounts and years)	Number of Shares	Weighted- Average Exercise Price Per Share		Weighted- Average Remaining Contractual Term (years)	Aggregate Intrinsic Value
Outstanding as of December 31, 2022	432,443	$	11.60

Options exercised	(155,205)	$	11.04		$	8,247

Outstanding as of June 30, 2023	277,238	$	11.92	3.60	$	14,485
Vested or expected to vest at June 30, 2023	277,234	$	11.92	3.60	$	14,485
Options exercisable at June 30, 2023	270,571	$	11.88	3.54	$	14,147

Schedule of nonvested equity stock and stock units activity

The following table reflects the activity related to nonvested equity stock and stock units for the six months ended June 30, 2023:


Nonvested Equity Stock and Stock Units	Shares	Weighted- Average Grant-Date Fair Value
Nonvested at December 31, 2022	4,718,060	$	22.78
Granted	1,174,026	$	46.01
Vested	(1,516,751)	$	24.29
Forfeited	(328,194)	$	26.62
Nonvested at June 30, 2023	4,047,141	$	31.32