Excess Tax Expense - Share Based Compensation

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RTSR Modifier

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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 for defined contribution plan.

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

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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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- Definition

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

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- Definition

Amount of cash outflow for realized tax benefit related to deductible compensation cost reported on the entity's tax return for equity instruments in excess of the compensation cost for those instruments recognized for financial reporting purposes.

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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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- 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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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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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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The number of shares or units of entity securities issued in the transaction in which equity securities were issued to pay for goods or nonemployee services.

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Share-Based Compensation (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended			36 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	May 12, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock available for awards, shares							10,000,000
Common stock reserved for future awards, shares	10,007,832					10,007,832
Stock-based employee compensation expense	$ 13.5	$ 16.3	$ 15.2
Related tax benefits	3.3	4.0	3.7
Excess Tax Benefit from Share-based Compensation, Operating Activities		0.8	1.0
Unrecognized compensation cost related to nonvested awards	$ 19.1					$ 19.1
Weighted-average remaining requisite service period, years	1 year 10 months 24 days
RTSR Modifier	25.00%
Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay	3.00%
401(k) match, profit sharing and non-elective expense	$ 37.8	$ 37.5	$ 37.6
Excess Tax Expense - Share Based Compensation	$ 0.4
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted	235,100
Shares nonvested	478,227	302,606				478,227
Shares vesting period, (years)						3 years
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted	528,729	552,389	514,338
Shares nonvested	1,384,336	1,503,251				1,384,336
Performance Shares \| NOEPS
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of shares granted	$ 11.7	$ 11.7	$ 9.2
Performance Shares \| CVI
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of shares granted	$ 2.6	$ 2.5	$ 2.4
Omnibus Plan \| Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Units issued	210,273
Director Plan \| Non-Employee Director Award
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares nonvested	67,806					67,806
2018 Award \| Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted			158,689
Fair value of shares granted			$ 3.5
Shares nonvested	119,333					119,333
2018 Award \| Performance Shares \| NOEPS
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares nonvested	347,479					347,479
2018 Award \| Performance Shares \| CVI
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares nonvested	80,185					80,185
2019 Award \| Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted		166,031
Fair value of shares granted		$ 4.1
Shares nonvested	135,170					135,170
2019 Award \| Performance Shares \| NOEPS
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares nonvested	384,680					384,680
2019 Award \| Performance Shares \| CVI
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares nonvested	88,769					88,769
2020 award \| Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted	235,100
Fair value of shares granted	$ 6.1
Shares nonvested	223,724					223,724
2020 award \| Performance Shares \| NOEPS
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares nonvested	392,619					392,619
2020 award \| Performance Shares \| CVI
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares nonvested	90,604					90,604
Subsequent Event \| Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares vesting period, (years)				3 years	3 years
Subsequent Event \| Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares vesting period, (years)					3 years