Represents the percentage of target amount as a actual payment.

No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Award Cliff Vesting Period

+ References

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
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-Section 50
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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-Paragraph 2
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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
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- Definition

Discount rate from fair value on purchase date that participants pay for shares.

+ References

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

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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Paragraph 2
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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.

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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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Share-Based Payments - Narrative (Details) - USD ($)	12 Months Ended			18 Months Ended
Share-Based Payments - Narrative (Details) - USD ($)	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2020	Jun. 30, 2019
Restricted Stock Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award cliff vesting period	4 years
Granted (in dollars per share)	$ 45.97	$ 48.18	$ 41.39
Fair value of awards vested	$ 2,800,000	$ 2,400,000	$ 2,200,000
Unrecognized compensation costs	$ 2,400,000			$ 2,400,000
Unrecognized compensation costs, period of recognition	1 year 9 months 21 days
Restricted Stock Awards \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	3 years
Restricted Stock Awards \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	4 years
Stock Performance Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	3 years
Granted (in dollars per share)	$ 47.79	$ 42.87	$ 35.73
Fair value of awards vested	$ 3,400,000	$ 6,100,000	$ 4,700,000
Unrecognized compensation costs	$ 800,000			$ 800,000
Unrecognized compensation costs, period of recognition	6 months 25 days
Stock Performance Awards \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of target amount as actual payment	0.00%
Stock Performance Awards \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of target amount as actual payment	150.00%
The 1999 Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payment awards, number of shares authorized (in shares)	1,400,000			1,400,000
Discount from market price rate	15.00%			85.00%	100.00%
Number of shares available for grant (in shares)	318,101			318,101
Share-based payment arrangement, expense	$ 200,000	100,000	0
The 2014 Stock Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payment awards, number of shares authorized (in shares)	1,900,000			1,900,000
Number of shares available for grant (in shares)	897,798			897,798
Share-based payment arrangement, expense	$ 6,100,000	5,900,000	4,400,000
Share-based payment arrangement, expense, tax benefit	$ 2,100,000	$ 2,300,000	$ 1,900,000