Increase (Decrease) In Share Based Compensation Expense

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- Definition

Share-Based Compensation Arrangement By Share-Based Payment Award, Options, Grants In Period, Grant Date Fair Value

+ References

No definition available.

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- Definition

Share-based Compensation Arrangement Age Requirement to Vest Over Original Vesting Period

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No definition available.

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- Definition

Share-based Compensation Arrangement Time in Service Requirement to Vest Over Original Vesting Period

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No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, vested

+ References

No definition available.

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- Definition

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

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-Name Accounting Standards Codification
-Topic 718
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- Definition

Amount, after tax, of expense for award under share-based payment arrangement.

+ References

No definition available.

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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.

+ References

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- Definition

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

+ 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.

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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

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.

+ References

No definition available.

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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.

+ References

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- Definition

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

+ References

No definition available.

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- Definition

Number of options outstanding, including both vested and non-vested options.

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- Definition

Number of fully vested and expected to vest exercisable options that may be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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- Definition

Number of fully vested and expected to vest options outstanding that can be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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- Definition

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

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- Definition

Number of non-vested options forfeited.

+ References

No definition available.

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Stock-Based Compensation Plans (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options, outstanding, number (in shares)	114,943		114,943
Options, grants in period, weighted average grant date fair value	$ 2.0		$ 2.0
Nonvested awards, compensation cost not yet recognized, period for recognition			3 years
Unearned compensation expense	$ 0.3		$ 0.3
Options, grants in period, gross (in shares)			0	0
Grants in period, vested (in shares)			0	0
Plan 2010
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized to issue under share based compensation plans (in shares)	8,700,000		8,700,000
Common stock available under stock option plan (in shares)	1,526,608		1,526,608
Share-based compensation arrangement age requirement to vest over original vesting period			55 years
Time in service requirement to vest over original vesting period			10 years
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			3 years
Nonvested awards, compensation cost not yet recognized, period for recognition			1 year
Nonvested awards, compensation cost not yet recognized	$ 31.5		$ 31.5		$ 24.3
Equity instruments other than options, vested in period, fair value	0.3	$ 0.2	16.5	$ 14.0
Allocated share-based compensation expense, net of tax	5.5	4.4	17.4	10.9
Allocated share-based compensation expense	$ 7.2	$ 5.7	$ 22.5	$ 14.1
Shares forfeited (in shares)			115,302	100,033
Decrease in stock-based compensation expense			$ 4.5	$ 5.4
Equity instruments other than options, nonvested, number (in shares)	1,754,343		1,754,343		1,530,214
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			36 months
Equity instruments other than options, nonvested, number (in shares)	687,000		687,000
Award requisite service period (in years)			3 years
Estimated vesting of shares based on performance shares (in shares)	689,000		689,000
Minimum \| Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rights, percentage			0.00%
Options, vested and expected to vest, exercisable, number (in shares)	0		0
Maximum \| Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rights, percentage			200.00%
Options, vested and expected to vest, exercisable, number (in shares)	1,374,000		1,374,000