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).

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 (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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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

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

+ 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 (c)(2)(iii)(2)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (d)(2)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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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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Share-Based and Other Compensation - Market-Measure Based RSUs (Details) - Market measure-based Restricted Stock Units (RSUs) [Member] - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	12 Months Ended
	Jan. 31, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	154,267
Fair value per share on valuation date (in dollars per share)		$ 85.08
Vested (in shares)		(270,054)	(265,737)	(265,918)
Nonvested Restricted Stock Units RSU [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)		154,267	231,191	601,012
Fair value per share on valuation date (in dollars per share)		$ 85.08	$ 71.12	$ 68.51
Vested (in shares)		(230,334)
Vested Restricted Stock Units RSU [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)		38,313
Vested (in shares)		(230,334)
Total Fair Value at Vest Date		$ 19,471	$ 18,703	$ 18,906