Share-Based Compensation Arrangements by Share-Based Payment Award, Performance Shares Payout Rate

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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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- Definition

Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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Amount of noncash expense for share-based payment arrangement.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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- Definition

Gross number of share options (or share units) granted during the period.

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Number of shares used to settle grantee's tax withholding obligation for award under share-based payment arrangement.

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- Definition

Number of shares issued during the period as a result of an employee stock purchase plan.

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Stock-Based Compensation Plans - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants in period (in shares)			0	0
Stock-based compensation expense	$ 6,367	$ 8,061	$ 20,790	$ 22,943
Stock-based compensation expense, tax benefits	$ 900	$ 1,400
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Incentive plan, total intrinsic value of stock options exercised			7,800	$ 14,300
LTIP Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense			$ 400
Number of shares vested (in shares)			10,457
Shares withheld to pay employees' portion of minimum payroll withholding taxes (in shares)			4,527
Total Shareholder Return Awards (TSRs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares vested (in shares)			782,588
Shares withheld to pay employees' portion of minimum payroll withholding taxes (in shares)			205,373
Payout rate	200.00%		200.00%
Vesting performance period			3 years
Unrecognized compensation costs	$ 21,300		$ 21,300
Unrecognized compensation costs, weighted average recognition period			2 years
Restricted Share Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares vested (in shares)			522,608
Shares withheld to pay employees' portion of minimum payroll withholding taxes (in shares)			155,031
Unrecognized compensation costs	$ 23,500		$ 23,500
Unrecognized compensation costs, weighted average recognition period			1 year 10 months 24 days
2017 Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued under ESPP (in shares)			86,877	114,709
2020 Equity and Incentive Compensation Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense			$ 20,800	$ 22,900
Stock-based compensation expense, tax benefits			$ 3,100	$ 4,200