Represents the number of types of share-based awards outstanding to employees and directors.

No definition available.

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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-Section S99
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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.

+ 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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-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

Description of terms of share-based payment arrangement. Includes, but is not limited to, type of award or grantee and reason for issuance.

+ References

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- Definition

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).

+ 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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-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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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
-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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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.

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- Definition

Gross number of share options (or share units) granted during the period.

+ References

No definition available.

+ Details

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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- Definition

Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

+ References

No definition available.

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Share-Based Compensation - Additional Information (Details) $ / shares in Units, $ in Millions	1 Months Ended		3 Months Ended		9 Months Ended
	May 31, 2021 $ / shares shares	Mar. 31, 2021 $ / shares shares	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2021 USD ($) Type	Sep. 30, 2020 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Types of share based awards \| Type					4
Share based awards, description					We currently have four types of share-based awards outstanding to our employees and directors: stock options, restricted stock units, performance-based stock units, and market stock units.
Share-based compensation costs \| $			$ 2.2	$ 3.4	$ 8.1	$ 6.3
Stock Options \| Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Each of share based awards, vesting period		3 years
Stock options granted \| shares		150,000
Stock options, weighted average exercise price per share		$ 26.29
Stock options, weighted average grant date fair value per share		$ 13.21
Restricted Stock Units (RSUs) \| Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Each of share based awards, vesting period		3 years
Restricted stock units granted \| shares		83,000
Restricted stock units, weighted average grant date fair value per share		$ 23.90
Restricted Stock Units (RSUs) \| Independent Members of Board of Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Each of share based awards, vesting period	1 year
Restricted stock units granted \| shares	30,000
Restricted stock units, weighted average grant date fair value per share	$ 24.76
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Each of share based awards, vesting period					1 year
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Each of share based awards, vesting period					3 years