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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- Definition

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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- Definition

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

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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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

Percentage of vesting of award under share-based payment arrangement.

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- Definition

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		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Jun. 09, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 7,932	$ 14,372	$ 14,882	$ 20,957
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Incentive plan, total intrinsic value of stock options exercised			10,500	$ 6,000
Unrecognized compensation costs	$ 100		$ 100
Unrecognized compensation costs, weighted average recognition period			8 months 12 days
LTIP Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares vested			668,240
Shares withheld to pay employees' portion of minimum payroll withholding taxes			165,237
Restricted Share Awards (RSAs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares vested			88,913
Shares withheld to pay employees' portion of minimum payroll withholding taxes			28,233
Total Shareholder Return Awards (TSRs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares vested			199,413
Payout rate	93.00%		93.00%
Vesting performance period			3 years
Shares withheld to pay employees' portion of minimum payroll withholding taxes			53,033
Unrecognized compensation costs	$ 27,100		$ 27,100
Unrecognized compensation costs, weighted average recognition period			1 year 10 months 24 days
Total Shareholder Return Awards (TSRs) \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Payout rate	0.00%		0.00%
Total Shareholder Return Awards (TSRs) \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Payout rate	200.00%		200.00%
Restricted Share Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares vested			399,605
Vesting performance period			3 years
Award vesting rights percentage			33.00%
Shares withheld to pay employees' portion of minimum payroll withholding taxes			109,652
Unrecognized compensation costs	$ 30,100		$ 30,100
Unrecognized compensation costs, weighted average recognition period			2 years 1 month 6 days
2017 Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued under ESPP			72,228	60,362
2020 Equity and Incentive Compensation Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for grant					6,658,754
2016 Equity and Performance Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	7,900	14,400	$ 14,900	$ 21,000
Stock-based compensation expense, tax benefits	$ 1,400	$ 2,800	$ 2,800	$ 4,000