Lability-based award settlement payment date.

No definition available.

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- Definition

Vested undistributed restricted stock units.

+ References

No definition available.

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- Definition

Vested phantom shares payable in cash rather than converted to shares.

+ References

No definition available.

+ Details

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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
-Paragraph 1
-Subparagraph (b)
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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-Section S99
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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

Aggregate carrying value as of the balance sheet date of the liabilities for stock option plans and other equity-based compensation arrangements.

+ References

No definition available.

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- 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

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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- 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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- Definition

Date the equity-based award expires, in YYYY-MM-DD format.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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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.

+ 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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- 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

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

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-Publisher FASB
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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

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

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- Details

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- Details

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- Details

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Share-Based Compensation Plans (Narrative) (Details) - USD ($) $ in Millions		12 Months Ended
	Jan. 05, 2021	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares outstanding		73,500	139,600
Adjusted share-based compensation cost		$ 11.3	$ 6.9	$ 8.4
Share-based compensation cost, net of tax		8.5	$ 5.1	$ 6.3
Total unrecognized compensation cost		$ 19.3
Total unrecognized compensation cost, weighted-average period		2 years 4 months 24 days
Market Based Performance Stock Awards [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares granted		54,231	42,698
Restricted Stock [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award vesting period		5 years
RSUs [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares granted		23,600
2016 LTIP [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares authorized		2,803,242
Shares available for grant		1,040,066
Plan expiration date		Jul. 08, 2026
2016 LTIP [Member] \| Employee Stock Option [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award vesting period		3 years
Award expiration period		10 years
2016 Director Stock Unit Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares authorized		250,000
Shares available for grant		158,904
2016 Director Stock Unit Plan [Member] \| RSUs [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award vesting period		1 year
Number of shares granted		8,314	12,278
Number of shares outstanding		130,393	126,474
Vested director stock units		122,079	114,196
2020 Inducement Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares authorized		19,000
Shares available for grant		3,452
Plan expiration date		Dec. 14, 2030
2020 Inducement Plan [Member] \| Restricted Stock [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award vesting period		3 years
2006 Phantom Stock Unit Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares available for grant		0
Vested phantom shares		11,773
Total liability recorded for shares			$ 1.2
Liability-based award settlement payment date	Jan. 05, 2021
Number of shares outstanding		0
2006 Phantom Stock Unit Plan [Member] \| Maximum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award vesting period		3 years
2006 Phantom Stock Unit Plan [Member] \| Minimum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award vesting period		1 year