Share-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2021

Share-based Payment Arrangement [Abstract]

Schedule of Restricted Stock Awards ("RSAs")

Restricted Stock Awards (“RSAs”) generally vest in annual installments between one and three years from each grant date. The following table provides a summary of RSAs for the years ended December 31, 2021, 2020 and 2019:

	Number of Shares			Weighted-Average Grant Date Fair Value
Unvested at January 1, 2019		585,106		$	26.89
Granted		302,506			31.24
Vested		(312,462	)		26.99
Forfeited		(17,905	)		29.58
Unvested at December 31, 2019		557,245			29.10
Granted		672,689			18.18
Vested		(333,685	)		25.67
Forfeited		(61,991	)		28.97
Unvested at December 31, 2020		834,258			21.68
Granted		434,486			20.52
Vested		(456,357	)		19.08
Forfeited		(23,065	)		22.45
Unvested at December 31, 2021		789,322		$	22.52

Schedule of Performance Stock Units ("PSUs")

The following table provides a summary of PSUs for the years ended December 31, 2021, 2020 and 2019:

	Number of Shares			Weighted-Average Grant Date Fair Value
Unvested at January 1, 2019		537,936		$	31.16
Granted		314,858			34.28
Vested		(277,325	)		31.25
Forfeited		(672	)		42.05
Unvested at December 31, 2019		574,797			32.82
Granted		1,641,117			14.39
Vested		(973,891	)		20.00
Forfeited		(163,468	)		17.34
Unvested at December 31, 2020		1,078,555			18.70
Granted		327,416			27.16
Vested		(428,255	)		16.33
Forfeited		(5,642	)		20.29
Unvested at December 31, 2021		972,074		$	22.59

Schedule of Grant Date Fair Values of Awards Using Monte Carlo Simulation Valuation Model

The grant date fair values of the awards that are subject to the achievement of market conditions based on total shareholder return were determined using a Monte Carlo simulation valuation model with the following assumptions:

	Year Ended December 31,
	2021			2020		2019
Expected volatility(1)		60.0	%	22.0% - 65.0%		19.5% - 21.5%
Dividend yield(2)		—			—		—
Risk-free rate	0.2% - 0.3%			0.3% - 1.5%		1.8% - 2.4%
Expected term	3 years			1 - 4 years		3 years

(1) The weighted average expected volatility for the years ended December 31, 2021, 2020 and 2019 was 60.0%, 46.2% and 20.5%, respectively.

(2) Dividends are assumed to be reinvested in shares of our common stock and dividends will not be paid unless shares vest.