Stock-Based Compensation (Tables)

3 Months Ended

Mar. 31, 2021

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Summary of Nonvested Restricted Stock Units and Changes During the Period

Nonvested restricted stock units as of March 31, 2021, and changes during the three months ended March 31, 2021 (unaudited) were as follows:

	Shares		Weighted Average Grant-Date Fair Value
Nonvested as of December 31, 2020		51,276	$	33.24
Granted		313,502		34.45
Nonvested as of March 31, 2021		364,778	$	34.28

Schedule of Stock-Based Compensation Expense

The Company's stock-based compensation expense related to the restricted stock units for the three months ended March 31, 2021 and 2020 (unaudited), respectively, which is included in General and administrative expenses within the Condensed Consolidated Statements of Income (Loss), was as follows:

	Three Months Ended
(millions)	March 31, 2021		March 31, 2020
Stock-based compensation expense	$	0.8	$	0.3

The Company's stock-based compensation expense (net reduction of expense) related to PSU’s during the three months ended March 31, 2021 and 2020 (unaudited), respectively, which is included in General and administrative expenses within the Condensed Consolidated Statements of Income (Loss), was as follows:

	Three Months Ended
(millions)	March 31, 2021		March 31, 2020
Stock-based compensation expense	$	0.1	$	(3.2	)

Summary of Nonvested PSU's and Changes During the Period

Nonvested PSU’s as of March 31, 2021, and changes during the year ended March 31, 2021 (unaudited) was as follows:

	Shares			Weighted Average Grant-Date Fair Value
Nonvested as of December 31, 2020		200,218		$	35.27
Granted		50,868			34.97
Forfeited		(3,375	)		35.96
Nonvested as of March 31, 2021		247,711		$	35.20