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- Definition

Share based compensation arrangement by share based payment award options exercisable number performance conditions attached.

+ References

No definition available.

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- Definition

Share-based compensation shares authorized under stock equivalent units exercise price range number of exercisable options.

+ References

No definition available.

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- Definition

Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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- Definition

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

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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

Amount of cost to be recognized for option under share-based payment arrangement.

+ References

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- Definition

Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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- Definition

Amount of noncash expense for share-based payment arrangement.

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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

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

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

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.

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- Definition

Number of grantees affected by modification of award under share-based payment arrangement.

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- Definition

The number of shares reserved for issuance pertaining to the outstanding exercisable stock options as of the balance sheet date in the customized range of exercise prices for which the market and performance vesting condition has been satisfied.

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- Definition

The excess of the fair value of the modified award over the fair value of the award immediately before the modification.

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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.

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Stock-Based Compensation Plans - Additional Information (Detail) $ in Millions	3 Months Ended	12 Months Ended
	Dec. 31, 2020 USD ($) Employee shares	Dec. 31, 2020 USD ($) Stock_Plan shares	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option compensation		$ 5.8	$ 6.6	$ 4.9
Accrued liabilities	$ 129.8	$ 129.8	154.0
Stock Options Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of stock vesting period	2 years
Expiration term for stock granted		10 years
Aggregate number of shares of common stock reserved for issuance which can be granted \| shares	2,550,000	2,550,000
Number of stock option plans \| Stock_Plan		2
Number exercisable and fully vested \| shares	42,657	42,657
Fully vested stock options with performance conditions attached \| shares	15,611	15,611
Stock option compensation		$ 5.8	6.6	4.9
Total intrinsic value exercised		4.9	3.5	3.2
Total compensation cost related to non-vested stock options not yet recognized	$ 6.8	$ 6.8
Expected compensation cost recognized over the weighted-average period		1 year 7 months 2 days
Current tax benefit related to stock option compensation		$ 1.6	1.5
Share-based Goods and Nonemployee Services Transaction, Modification of Terms, Incremental Compensation Cost	$ 2.4
Number of Grantees Affected \| Employee	14
Stock Options Plan [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of stock vesting period		2 years
Stock Options Plan [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of stock vesting period		5 years
Stock Equivalent Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of stock vesting period	2 years
Expiration term for stock granted		10 years
Fully vested stock options with performance conditions attached \| shares	46,614	46,614
Total intrinsic value exercised		$ 6.3	7.3	2.7
Expected compensation cost recognized over the weighted-average period		1 year 11 months 23 days
Accrued liabilities	$ 17.2	$ 17.2
Number of exercisable SEUs \| shares	53,146	53,146
Compensation cost		$ 1.9	$ 20.1	$ 5.7
Number of Grantees Affected \| Employee	61
Stock Equivalent Units [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of stock vesting period		2 years
Stock Equivalent Units [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of stock vesting period		5 years