Share-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2020

Share-based Payment Arrangement [Abstract]

Schedule of Restricted Stock Units Activity

The following table summarizes RSU Equity Award activity for the years ended December 31, 2020, 2019 and 2018:

	RSU Equity Awards (in thousands)	Weighted Average Grant-Date Fair Value per Share
For the Year Ended December 31, 2018
Unvested at the beginning of the period	179	$115.36
Granted (1)	87	$144.86
Vested (2)	(51)	$103.83
Forfeited	(5)	$114.32
Unvested at the end of the period	210	$130.39
For the Year Ended December 31, 2019
Unvested at the beginning of the period	210	$130.39
Granted (1)	188	$85.96
Vested (2)	(106)	$126.75
Forfeited	(23)	$110.55
Unvested at the end of the period	269	$102.48
For the Year Ended December 31, 2020
Unvested at the beginning of the period	269	$102.48
Granted (1)	562	$21.07
Vested (2)	(132)	$105.14
Forfeited	(22)	$96.84
Unvested at the end of the period	677	$34.57

(1)Includes 111.2 thousand, 39.9 thousand and 20.8 thousand target performance-based RSU Equity Awards for the years ended December 31, 2020, 2019 and 2018, respectively.

(2)The fair value of shares vested was $1.6 million, $7.3 million and $6.3 million during the years ended December 31, 2020, 2019 and 2018, respectively.

Schedule of Shares that Vested and Did Not Vest

The following table summarizes the shares that vested and did not vest as a result of the Company’s performance as compared to its peers.

	Years Ended December 31,
Performance-based Equity Awards	2020	2019		2018
Vesting Multiplier	50% - 100%	100	%	142	%
Target	21,920	8,878		8,300
Vested at end of performance period	11,372	8,878		11,786
Did not vest at end of performance period	10,548	—		—

Schedule of Fair Value Inputs

The following table summarizes the assumptions used and the resulting grant date fair value per performance-based RSU Equity Award granted during the years ended December 31, 2020, 2019 and 2018:

Performance-based Awards	June 29, 2020		January 31, 2020		January 31, 2019		May 10, 2018
Expected term (in years)	2.5		2.9		2.9		2.6
Expected volatility	113.2	%	54.8	%	47.9	%	51.6	%
Risk-free interest rate	0.2	%	1.3	%	2.4	%	2.6	%
Dividend yield	—	%	—	%	—	%	—	%

The following table summarizes the assumptions used, the resulting acquisition date fair value per Cash SAR, and the expiration dates for the grants that occurred during periods presented below:

	2019		2018		2017		2016
Expected term (in years)	5.4		4.5		1.9		1.1
Expected volatility	60.7	%	56.9	%	58.6	%	68.1	%
Risk-free interest rate	1.7	%	1.7	%	1.6	%	1.5	%
Dividend yield	—	%	—	%	—	%	—	%
Expiration date	March 17, 2026		March 17, 2025		March 23, 2022		March 17, 2021

Schedule of Cash-Settleable RSUs

The table below summarizes the Cash-Settled RSU Award activity for the years ended December 31, 2020, 2019 and 2018:

	Cash-Settled RSU Awards (in thousands)	Weighted Average Grant-Date Fair Value per Share
For the Year Ended December 31, 2018
Unvested at the beginning of the period	61	$123.82
Granted	35	$164.77
Vested	(28)	$116.67
Forfeited	(2)	$161.50
Unvested at the end of the period	66	$147.59
For the Year Ended December 31, 2019
Unvested at the beginning of the period	66	$147.59
Granted	44	$105.08
Vested	(16)	$155.29
Forfeited	(8)	$145.71
Unvested at the end of the period	86	$124.22
For the Year Ended December 31, 2020
Unvested at the beginning of the period	86	$124.22
Granted	142	$26.84
Vested	(16)	$160.39
Did not vest at end of performance period	(16)	$163.55
Forfeited	—	$—
Unvested at the end of the period	196	$47.56

Summary of Liability for Cash-Settled RSU Awards

The following table summarizes the Company’s liability for Cash-Settled RSU Awards and the classification in the consolidated balance sheets for the periods indicated:

	December 31,
	2020	2019
	(In thousands)
Other current liabilities	$182	$966
Other long-term liabilities	1,336	2,089
Total Cash-Settled RSU Awards	$1,518	$3,055

Schedule of Performance-Based Cash-Settled RSUs Awards

As of December 31, 2020, the Company had the following performance-based Cash-Settled RSU Awards outstanding:

	Target Awards Outstanding	Potential Minimum Units Vesting	Potential Maximum Units Vesting
	(In thousands)
Vesting in 2021	35	—	70
Vesting in 2022	111	—	334
Other	50	50	50
Total Cash-Settled RSU Awards	196	50	454

Schedule of Cash-Settled SARs

The table below summarizes the Cash SAR activity for the year ended December 31, 2020.

	Stock Appreciation Rights (in thousands)	Weighted Average Exercise Prices	Weighted Average Remaining Life (In years)	Aggregate Intrinsic Value (In millions)
For the Year Ended December 31, 2019
Outstanding, beginning of period	—	$—
Granted	—	$—
Reissued	368	$100.34
Exercised	—	$—
Forfeited	—	$—
Expired	—	$—
Outstanding, end of period	368	$100.34	4.4	$—
Vested, end of period	368	$100.34	—	$—
Vested and exercisable, end of period	—	$—	—	$—
For the Year Ended December 31, 2020
Outstanding, beginning of period	368	$100.34
Granted	—	$—
Exercised	—	$—
Forfeited	—	$—
Expired	—	$—
Outstanding, end of period	368	$100.34	3.4	$—
Vested, end of period	368	$100.34	—	$—
Vested and exercisable, end of period	—	$—	—	$—

Schedule of Share-based Compensation Expense

The following table presents share-based compensation expense (benefit), net for each respective period:

	Years Ended December 31,
	2020	2019	2018
RSU Equity Awards	$13,030	$14,322	$9,460
Cash-Settled RSU Awards	(771)	1,021	336
Cash SARs	(3,344)	443	—
	8,915	15,786	9,796
Less: amounts capitalized to oil and gas properties	(6,252)	(4,704)	(3,434)
Total share-based compensation expense, net	$2,663	$11,082	$6,362