Equity Incentive Plans and Stock-Based Compensation (Tables)

3 Months Ended

Mar. 31, 2022

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, 2021						10,492,178




Nonvested equity stock and stock units granted (1) (2)						(2,869,504)
Nonvested equity stock and stock units forfeited (1)						663,083
Total shares available for grant as of March 31, 2022						8,285,757

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(1) For purposes of determining the number of shares available for grant under the 2015 Equity Incentive Plan (the “2015 Plan”) against the maximum number of shares authorized, each restricted stock granted reduces the number of shares available for grant by 1.5 shares and each restricted stock forfeited increases shares available for grant by 1.5 shares.

(2) Amount includes approximately 0.5 million shares that have been reserved for potential future issuance related to certain performance unit awards granted in the first quarter of 2022 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 three months ended March 31, 2022 and information regarding stock options outstanding, exercisable, and vested and expected to vest as of March 31, 2022.


	Options Outstanding
(In thousands, except 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, 2021	549,581	$	10.71

Options exercised	(58,401)	$	5.36

Outstanding as of March 31, 2022	491,180	$	11.35	4.41	$	10,089
Vested or expected to vest at March 31, 2022	491,009	$	11.35	4.41	$	10,086
Options exercisable at March 31, 2022	454,703	$	11.20	4.18	$	9,407

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 three months ended March 31, 2022:


Nonvested Equity Stock and Stock Units	Shares	Weighted- Average Grant-Date Fair Value
Nonvested at December 31, 2021	4,718,385	$	16.62
Granted	1,594,236	$	28.09
Vested	(1,503,259)	$	13.80
Forfeited	(96,187)	$	18.04
Nonvested at March 31, 2022	4,713,175	$	21.37