Number Of Consecutive Trading Days For Total Shareholder Return (TSR) Calculation

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- Definition

Share-Based Compensation Arrangement By Share-based Payment Award, Equity Instruments Other Than Options, Vested Target

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term for Expected Volatility Rate

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- Definition

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

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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

Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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 non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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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

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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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

Number of shares authorized for issuance under share-based payment arrangement.

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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

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

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- Definition

Expected term of 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

Number of new stock issued during the period.

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Stock Based Compensation - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
2017 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum shares issuable (in shares)	43,170,000
Common shares reserved for issuance (in shares)	31,367,872	5,540,536
2017 Plan \| Non-employee director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock issued (in shares)		507,821
2017 Plan \| Non-employee director \| Director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock issued (in shares)	687,503
2017 Plan \| Employee \| Employee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock issued (in shares)	2,689,394
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares outstanding, unvested restricted stock (in shares)	1,909,107	1,603,766	837,123	507,536
Non-cash compensation expense	$ 4.3	$ 3.8	$ 2.2
Unrecognized compensation expense	$ 5.1	5.9
Weighted average period to recognize the unrecognized compensation expense	1 year 8 months 12 days
Fair value of shares vested	$ 2.5	$ 1.8	$ 1.3
Requisite service period	3 years
Shares vested (in shares)	621,438	287,611	205,080
Restricted Stock \| 2010 Stock Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares outstanding, unvested restricted stock (in shares)	0
Restricted Stock \| 2017 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares outstanding, unvested restricted stock (in shares)	1,909,107	1,603,766
Restricted Stock \| 2017 Plan \| Employee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock issued (in shares)		1,881,380
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of shares vested	$ 3.7
Expected term for expected volatility rate	3 years
Shares vested (in shares)	974,074
Vested shares target (in shares)	842,792
Performance Shares \| 2017 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common shares reserved for issuance (in shares)	6,168,886	4,798,517
Non-cash compensation expense	$ 5.5	$ 5.0	$ 2.9
Unrecognized compensation expense	$ 7.6	$ 5.7	$ 4.5
Weighted average period to recognize the unrecognized compensation expense	1 year 9 months 18 days
Award vesting period	3 years	3 years
Number of consecutive trading days for Total Shareholder Return (TSR) calculation	30 days
Fair value assumptions, expected term	3 years
Performance Shares \| 2017 Plan \| Relative TSR performance Is Less than the 30th percentile
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rights percentage	0.00%
Performance Shares \| 2017 Plan \| Relative TSR performance Is equal to the 50th percentile
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rights percentage	100.00%
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares outstanding, unvested restricted stock (in shares)	1,016,252	441,746	0
Unrecognized compensation expense	$ 2.7	$ 1.8
Weighted average period to recognize the unrecognized compensation expense	1 year 8 months 12 days
Fair value of shares vested	$ 0.5
Requisite service period	3 years	3 years
Shares vested (in shares)	147,254	0
RSUs \| 2017 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common shares reserved for issuance (in shares)	1,016,252	441,746
Non-cash compensation expense	$ 1.7	$ 0.9