Stock-Based Compensation Plans - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 6,950	$ 6,585
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Incentive plan, total intrinsic value of stock options exercised	300	$ 5,300
Unrecognized compensation costs	$ 100
Unrecognized compensation costs, weighted average recognition period	10 months 24 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%
Vesting performance period	3 years
Shares withheld to pay employees' portion of minimum payroll withholding taxes	53,033
Unrecognized compensation costs	$ 31,500
Unrecognized compensation costs, weighted average recognition period	2 years 6 months
Restricted Share Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares vested	327,491
Shares withheld to pay employees' portion of minimum payroll withholding taxes	103,839
Unrecognized compensation costs	$ 33,700
Unrecognized compensation costs, weighted average recognition period	2 years 4 months 24 days
2017 Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued under ESPP	31,794	32,174
2016 Equity and Performance Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 7,000	$ 6,600
Stock-based compensation expense, tax benefits	$ 1,400	$ 1,200

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

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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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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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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting 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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Number of shares issued during the period as a result of an employee stock purchase plan.

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