Stock-based Compensation Plans (Tables)

6 Months Ended

Jun. 30, 2022

Allocation of Stock-Based Compensation by Functional Category

The following details the allocation of stock-based compensation to functional expense categories (in thousands):

	Three Months Ended June 30,				Six Months Ended June 30,
	2022		2021		2022		2021
Direct operating expense	$	362	$	340	$	711	$	667
Brokered natural gas and marketing expense		686		443		1,205		893
Exploration expense		318		362		770		748
General and administrative expense		10,270		9,382		21,843		18,787
Total stock-based compensation expense	$	11,636	$	10,527	$	24,529	$	21,095

Restricted Stock and Restricted Stock Units Outstanding

The following is a summary of the status of our non-vested restricted stock outstanding at June 30, 2022:

Schedule of Share Based Payment Award Performance Stock Awards Valuation Assumptions

The following assumptions were used to estimate the fair value of TSR-PSUs granted during first six months 2022 and 2021:

	Six Months Ended June 30,
	2022			2021
Risk-free interest rate		1.4	%		0.2	%
Expected annual volatility		68	%		75	%
Grant date fair value per unit	$	27.90		$	12.58

Performance-based Internal Performance Awards

Summary of Non-Vested Awards Activities

The following is a summary of our non-vested internal performance awards outstanding at June 30, 2022:

	Number of Units			Weighted Average Grant Date Fair Value
Outstanding at December 31, 2021		1,095,355		$	7.80
Units granted (a)		153,089			20.38
Vested and issued (b)		(243,482	)		9.64
Forfeited		—			—
Outstanding at June 30, 2022		1,004,962		$	9.27

Performance Based TSR - PSUs

Summary of Non-Vested Awards Activities

The following is a summary of our non-vested TSR-PSUs award activities:

	Number of Units			Weighted Average Grant Date Fair Value
Outstanding at December 31, 2021		1,147,994		$	7.60
Units granted (a)		111,828			27.90
Vested and issued (b)		(314,152	)		11.34
Forfeited		—			—
Outstanding at June 30, 2022		945,670		$	8.76

(a)	These amounts reflect the number of performance units granted. The actual payout of shares may be between zero and 200% of the performance units granted depending on the total shareholder return ranking compared to our peer companies at the vesting date.
(b)	Includes TSR-PSUs awards granted in 2019 where the return on our common stock was 127% and therefore, the performance multiple and actual payout was 183%.