Common Stock Common Stock (Tables)

6 Months Ended

Jun. 30, 2020

Equity [Abstract]

Share-based Payment Arrangement, Cost by Plan [Table Text Block]

The impact of our stock-based compensation plans on our results of operations was $6.4 million and $12.0 million for the three and six months ended June 30, 2020, respectively, and $7.6 million and $12.3 million for the three and six months ended June 30, 2019, respectively.

Share-based Payment Arrangement, Restricted Stock and Restricted Stock Unit, Activity [Table Text Block]

The following table presents the changes in non-vested time-based RSUs to all employees, including executive officers, for the six months ended June 30, 2020:

	Shares		Weighted-Average Grant Date Fair Value per Share
Non-vested at December 31, 2019	795,926		$	45.51
Granted	1,033,498		11.69
Vested	(394,007	)	42.71
Forfeited	(140,403	)	23.36
Non-vested at June 30, 2020	1,295,014		21.77

The following table presents the weighted-average grant date fair value per share and related information as of/for the periods presented:

	As of/Six Months Ended June 30,
	2020		2019
	(in thousands, except per share data)
Total intrinsic value of time-based awards vested	$	5,432	$	10,424
Total intrinsic value of time-based awards non-vested	16,110		30,815
Market price per share as of June 30	12.44		36.06
Weighted-average grant date fair value per share	11.69		40.47

Restricted Stock Awards, Market-Based, Valuation assumptions [Table Text Block]

The Compensation Committee awarded a total of 289,494 market-based PSUs to our executive officers during the six months ended June 30, 2020. In addition to continuous employment, the vesting of these PSUs is contingent on a combination of absolute stock performance and our total stockholder return ("TSR"), which is essentially our stock price change, including any dividends over a three-year period ending on December 31, 2022, as compared to the TSR of a group of peer companies over the same period. The PSUs will result in a payout between zero and 250 percent of the target PSUs awarded. The weighted-average grant date fair value per PSU granted was computed using the Monte Carlo pricing model using the following assumptions:

	Six Months Ended June 30,
	2020			2019
Expected term of award (in years)	3			3
Risk-free interest rate	1.4		%	2.5		%
Expected volatility	46.6		%	41.4		%
Weighted-average grant date fair value per share	$	33.52		$	56.68

The expected term of the awards was based on the requisite service period. The risk-free interest rate was based on the U.S. Treasury yields in effect at the time of grant and extrapolated to approximate the life of the award. The expected volatility was based on our historical volatility.

SRC Performance Stock Units. Terms of the SRC PSUs are substantially the same as PDC PSUs, except that the awards do not require continuous employment and the performance period associated with the awards of January 1, 2019 through December 31, 2021 predates the grant date. The fair value of the SRC PSU awards was determined on the grant date of January 13, 2020 using the Monte Carlo pricing model using the following assumptions:

	Six Months Ended June 30,
	2020
Expected term of awards (in years)	2
Risk-free interest rate	1.6		%
Expected volatility	56.9		%
Weighted-average grant date fair value per share	$	33.35

Schedule of Nonvested Performance-based Units Activity [Table Text Block]

The following table presents the change in non-vested market-based awards, including SRC PSUs, during the six months ended June 30, 2020:

	Shares		Weighted-Average Grant Date Fair Value per Share
Non-vested at December 31, 2019	221,142		$	61.61
Granted	445,422		32.96
Forfeited	(11,014	)	40.69
Non-vested at June 30, 2020	655,550		42.49

The following table presents the weighted-average grant date fair value per share and related information as of/for the periods presented:

	As of/Six Months Ended June 30,
	2020		2019
	(in thousands, except per share data)
Total intrinsic value of market-based awards non-vested	$	8,155	$	8,731
Market price per common share as of June 30,	12.44		36.06
Weighted-average grant date fair value per share	32.96		56.68

Share-based Payment Arrangement, Stock Appreciation Right, Activity [Table Text Block]

The SARs vest ratably over a three-year period and may generally be exercised at any point after vesting through ten years from the date of issuance. Pursuant to the terms of the awards, upon exercise, the executive officers will receive, in shares of common stock, the excess of the market price of the award on the date of exercise over the market price of the award on the date of issuance. The following table presents the change in SARs during the six months ended June 30, 2020:

	Shares		Weighted-Average Grant Date Fair Value per Share
Outstanding at December 31, 2019	290,258		$	46.64
Exercised	(7,807	)	24.44
Expired	(71,776	)	40.83
Outstanding at June 30, 2020	210,675		49.45

All outstanding SARs as of June 30, 2020 have vested and the related compensation cost has been fully recognized.