Represents the number of equity stock based compensation.

No definition available.

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- Definition

This represents Average closing stock price.

+ References

No definition available.

+ Details

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- Definition

Share based compensation arrangement by share based payment award number of shares authorized average trading days.

+ References

No definition available.

+ Details

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- Definition

The percentage of target shares, an employee can earn, under the plan.

+ References

No definition available.

+ Details

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- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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-Section 50
-Paragraph 1
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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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.

+ References

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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.

+ References

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-Publisher FASB
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-SubTopic 10
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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 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).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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-Section 50
-Paragraph 2
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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.

+ References

No definition available.

+ Details

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- Definition

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

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-Paragraph 2
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Balance Type:	na
Period Type:	instant

- 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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

Intrinsic value of vested award under share-based payment arrangement. Excludes share and unit options.

+ References

No definition available.

+ Details

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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Period Type:	duration

- Details

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- Details

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Balance Type:
Period Type:

- Details

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- Details

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Stock-Based Compensation - Additional Information (Details) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2020 USD ($) plan $ / shares shares	Dec. 31, 2019 USD ($) day $ / shares	Dec. 31, 2018 USD ($) $ / shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of equity stock based compensation plans (plan) \| plan	2
Stock based compensation expense	$ 5.7	$ 4.4	$ 3.2
Unrecognized stock-based compensation expense	6.9
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Intrinsic value of options exercised	$ 0.7	$ 0.2	$ 1.3
Performance awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted at target (in dollars per share) \| $ / shares	$ 34.10	$ 39.26	$ 34.52
Intrinsic value of common stock at the time of vesting	$ 4.8	$ 0.2	$ 1.0
Unrecognized stock-based compensation expense	$ 4.0
Remaining weighted average vesting period	1 year 6 months
Time-vested stock awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted at target (in dollars per share) \| $ / shares	$ 26.75	$ 34.22	$ 30.22
Intrinsic value of common stock at the time of vesting	$ 2.5	$ 3.4	$ 3.0
Unrecognized stock-based compensation expense	$ 2.9
Remaining weighted average vesting period	1 year 6 months
Long-Term Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares permitted for granting (in shares) \| shares	1,500,000
Long-Term Incentive Plan \| Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award expiration period	10 years
Long-Term Incentive Plan \| Performance awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of trading days (day) \| day		30
Average closing stock price (in dollar per share) \| $ / shares	$ 33.57
Granted at target (in dollars per share) \| $ / shares	$ 26.75
Service period	2 years 8 months 12 days
Long-Term Incentive Plan \| Performance awards \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of potential target shares awarded	0.00%
Long-Term Incentive Plan \| Performance awards \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of potential target shares awarded	200.00%
Long-Term Incentive Plan \| Time-vested stock awards \| Employee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Service period	3 years
Long-Term Incentive Plan \| Time-vested stock awards \| Nonemployee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	1 year
Service period	1 year	1 year	3 years