Stock-Based Compensation

The Company grants equity-based awards to employees, non-employee directors, and consultants that may include, but are not limited to, RSA's, restricted stock units ("RSU's"), performance stock units ("PSU's") and stock options. Stock-based compensation expense related to manufacturing employees and administrative employees is included within the Cost of goods sold and Payroll and benefits line items, respectively, in the Condensed Consolidated Statements of Operations. Stock-based compensation expense related to non-employee directors and consultants is included within the General and administrative line item in the Condensed Consolidated Statements of Operations.

Total stock-based compensation expense for the three months ended March 31, 2020 and 2019 was as follows:



	Three Months Ended March 31,
(in thousands)	2020		2019
RSA expense	$	506	$	317
Total stock-based compensation expense	$	506	$	317

The amount of unrecognized compensation cost as of March 31, 2020, and the expected weighted-average period over which the cost will be recognized is as follows:



	As of March 31, 2020
(in thousands)	Unrecognized Compensation Cost		Expected Weighted- Average Period of Recognition (in years)
RSA expense	$	3,178	2.23
PSU expense	309		2.94
Total unrecognized stock-based compensation expense	$	3,487	2.29

Restricted Stock

Restricted stock is typically granted with vesting terms of three years. The fair value of RSA's and RSU's is determined based on the closing price of the Company’s common stock on the authorization date of the grant multiplied by the number of shares subject to the stock award. Compensation expense for RSA's is generally recognized on a straight-line basis over the entire vesting period. Compensation expense for RSU's is generally recognized on a straight-line basis over the service period of the award.

A summary of RSA activity under the Company's various stock compensation plans for the three months ended March 31, 2020 is presented below:



	Restricted Stock		Weighted-Average Grant Date Fair Value
Non-vested at January 1, 2020	451,344		$	10.65
Granted	218,524		$	5.34
Vested	(184,023	)	$	10.39
Forfeited	(265	)	$	10.84
Non-vested at March 31, 2020	485,580		$	8.36

Stock Options

Stock options generally vest over three years or upon satisfaction of performance-based conditions and have a contractual limit of five years from the date of grant to exercise. The fair value of stock options granted is determined on the date of grant using the Black-Scholes option pricing model and the related expense is recognized on a straight-line basis over the entire vesting period.

A summary of stock option activity for the three months ended March 31, 2020 is presented below:



	Number of Options Outstanding and Exercisable	Weighted-Average Exercise Price		Aggregate Intrinsic Value (in thousands)		Weighted-Average Remaining Contractual Term (in years)
Options outstanding, January 1, 2020	300,000	$	13.87
Options granted	—	—
Options exercised	—	—
Options expired / forfeited	—	—
Options outstanding, March 31, 2020	300,000	$	13.87	$	—	0.18
Options vested and exercisable, March 31, 2020	300,000	$	13.87	$	—	0.18

Performance Share Units

Compensation expense is recognized for PSU awards on a straight-line basis over the applicable service period, which is generally three years, based on the estimated fair value at the date of grant using a Monte Carlo simulation model. A summary of PSU activity for the three months ended March 31, 2020 is presented below:



	Units	Weighted-Average Grant Date Fair Value		Aggregate Intrinsic Value (in thousands)		Weighted-Average Remaining Contractual Term (in years)
PSU's outstanding, January 1, 2020	—	$	—
Granted	50,127	6.17
Vested / Settled	—	—
Forfeited / Canceled	—	—
PSU's outstanding, March 31, 2020	50,127	$	6.17	$	329	2.94