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Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Settled in Common Shares

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Aggregate number of common shares reserved for future issuance.

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Amount of cost for defined contribution plan.

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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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Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

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Percentage employer matches of the employee's percentage contribution matched.

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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 cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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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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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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

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Incentive Compensation and Benefit Plans - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions			12 Months Ended
	Jun. 09, 2021	Feb. 16, 2021	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Mar. 12, 2018
Defined Contribution Plan Disclosure [Line Items]
Employer matching contribution, percent of match			100.00%
Employer matching, maximum annual employee salary, matched			5.00%
Employee service requirements for plan participation			3 months
Contributions by employer			$ 3.2	$ 3.6
Restricted Stock
Defined Contribution Plan Disclosure [Line Items]
Grants in period (in shares)			252,503
Grants in period, weighted average grant date fair value (in dollars per share)			$ 18.45
Unearned deferred compensation expense, weighted average period			1 year 9 months 18 days
Restricted Stock Units (RSUs)
Defined Contribution Plan Disclosure [Line Items]
Grants in period (in shares)			143,949
Grants in period, weighted average grant date fair value (in dollars per share)			$ 17.46
Restricted Stock Units (RSUs) \| Executive Officers
Defined Contribution Plan Disclosure [Line Items]
Grants in period (in shares)		58,136
Award vesting period		3 years
Grants in period, weighted average grant date fair value (in dollars per share)		$ 16.65
Restricted Stock Units (RSUs) \| Executive Officer
Defined Contribution Plan Disclosure [Line Items]
Grants in period (in shares)		62,377
Award vesting period		3 years
Grants in period, weighted average grant date fair value (in dollars per share)		$ 16.65
Restricted Stock Units (RSUs) \| Non-employee Director
Defined Contribution Plan Disclosure [Line Items]
Grants in period (in shares)	19,719			33,453	3,439
Grants in period, weighted average grant date fair value (in dollars per share)	$ 22.82
Restricted Stock Units (RSUs) and Performance Stock Units (PSUs)
Defined Contribution Plan Disclosure [Line Items]
Unearned deferred compensation expense, weighted average period			1 year 9 months 18 days
Restricted Stock Units (RSUs) and Performance Stock Units (PSUs) \| Non-employee Director
Defined Contribution Plan Disclosure [Line Items]
Share-based compensation expense			$ 2.6	$ 0.5	$ 0.8
Unearned deferred compensation expense			$ 2.0
PSU \| Executive Officers
Defined Contribution Plan Disclosure [Line Items]
Grants in period (in shares)		58,136
Award vesting period		3 years
Grants in period, weighted average grant date fair value (in dollars per share)		$ 16.67
PSU \| Executive Officers \| Minimum
Defined Contribution Plan Disclosure [Line Items]
Actual numbers of awards earned as percent of target		50.00%
PSU \| Executive Officers \| Maximum
Defined Contribution Plan Disclosure [Line Items]
Actual numbers of awards earned as percent of target		150.00%
PSU \| Executive Officer
Defined Contribution Plan Disclosure [Line Items]
Grants in period (in shares)		62,377
Award vesting period		3 years
Grants in period, weighted average grant date fair value (in dollars per share)		$ 11.15
PSU \| Executive Officer \| Minimum
Defined Contribution Plan Disclosure [Line Items]
Actual numbers of awards earned as percent of target		50.00%
PSU \| Executive Officer \| Maximum
Defined Contribution Plan Disclosure [Line Items]
Actual numbers of awards earned as percent of target		100.00%
Stock-settled RSUs
Defined Contribution Plan Disclosure [Line Items]
Grants in period (in shares)			137,376
Grants in period, weighted average grant date fair value (in dollars per share)			$ 17.20
Stock-settled RSUs \| Non-employee Director
Defined Contribution Plan Disclosure [Line Items]
Grants in period (in shares)	13,146
Cash-settled RSUs
Defined Contribution Plan Disclosure [Line Items]
Grants in period (in shares)			6,573
Grants in period, weighted average grant date fair value (in dollars per share)			$ 22.82
Cash-settled RSUs \| Non-employee Director
Defined Contribution Plan Disclosure [Line Items]
Grants in period (in shares)	6,573
Class A common stock \| Restricted Stock
Defined Contribution Plan Disclosure [Line Items]
Grants in period (in shares)			252,503	6,591	3,882
Award vesting period				3 years	3 years
Grants in period, weighted average grant date fair value (in dollars per share)			$ 18.45	$ 15.17	$ 17.42
Share-based compensation expense			$ 2.8	$ 1.9	$ 5.9
Unearned deferred compensation expense			$ 2.5
Class A common stock \| Restricted Stock \| Share-based Payment Arrangement, Tranche Two
Defined Contribution Plan Disclosure [Line Items]
Grants in period (in shares)			203,692
Award vesting rights, percentage			50.00%
Class A common stock \| Restricted Stock \| Share-based Payment Arrangement, Tranche One
Defined Contribution Plan Disclosure [Line Items]
Grants in period (in shares)			48,811
Award vesting rights, percentage			50.00%
Award vesting period			2 years
Class A common stock \| Restricted Stock Units (RSUs) \| Non-employee Director
Defined Contribution Plan Disclosure [Line Items]
Shares settled in common shares				22,302	3,439
Shares settled in cash upon vesting				11,151
2018 Equity Plan \| Class A common stock
Defined Contribution Plan Disclosure [Line Items]
Shares reserved for future issuance (in shares)						3,333,333