Performance Awards Earned

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- Definition

Share-Based Compensation Arrangement By Share-Based Payment Award, Maximum Shares To Be Earned

+ References

No definition available.

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- Definition

Share-Based Compensation Arrangement By Share-Based Payment Award, Percentage Of Target Number Of Shares

+ 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=116856206&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.

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-Publisher FASB
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- References

No definition available.

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- Definition

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

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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)(1)(iv)(3)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

+ 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)(3)
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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

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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-Publisher FASB
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- Definition

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

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-Publisher FASB
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-Section 50
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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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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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STOCK-BASED COMPENSATION (RSU and RSA Rollforwards) (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Performance-Based Restricted Stock
Nonvested RSUs and RSAs, Number of Shares
Nonvested at the beginning of the period (in shares)	71,412
Granted (in shares)	0		0
Vested (in shares)	(23,804)
Forfeited (in shares)	0
Nonvested at the end of the period (in shares)	47,608	71,412
Nonvested RSUs and RSAs, Weighted Average Grant Date Fair Value
Nonvested at the beginning of the period (in dollars per share)	$ 340.25
Granted (in dollars per share)	0
Vested (in dollars per share)	340.25
Forfeited (in dollars per share)	0
Nonvested at the end of the period (in dollars per share)	$ 340.25	$ 340.25
Unrecognized compensation cost	$ 8.7
Weighted-average period for recognition of unrecognized compensation cost	2 years
Vested fair value	$ 8.2	$ 13.6
Market-Based Restricted Stock
Nonvested RSUs and RSAs, Number of Shares
Nonvested at the beginning of the period (in shares)	26,674
Granted (in shares)	0
Vested (in shares)	0
Forfeited (in shares)	0
Nonvested at the end of the period (in shares)	26,674	26,674
Nonvested RSUs and RSAs, Weighted Average Grant Date Fair Value
Nonvested at the beginning of the period (in dollars per share)	$ 340.25
Granted (in dollars per share)	0
Vested (in dollars per share)	0
Forfeited (in dollars per share)	0	$ 1,900,000
Nonvested at the end of the period (in dollars per share)	$ 340.25	$ 340.25
Unrecognized compensation cost	$ 1.0
Weighted-average period for recognition of unrecognized compensation cost	2 years 9 months 18 days
Return performance, percent of target stock price	110.00%
Maximum number of shares for earned (in shares)	44,545
Performance Awards Earned	29,601
RSUs
Nonvested RSUs and RSAs, Number of Shares
Nonvested at the beginning of the period (in shares)	201,568
Granted (in shares)	62,248
Vested (in shares)	(82,020)
Forfeited (in shares)	(36,857)
Nonvested at the end of the period (in shares)	144,939	201,568
Nonvested RSUs and RSAs, Weighted Average Grant Date Fair Value
Nonvested at the beginning of the period (in dollars per share)	$ 225.48
Granted (in dollars per share)	318.04
Vested (in dollars per share)	192.89
Forfeited (in dollars per share)	287.73
Nonvested at the end of the period (in dollars per share)	$ 267.85	$ 225.48
Unrecognized compensation cost	$ 24.4
Weighted-average period for recognition of unrecognized compensation cost	1 year 7 months 6 days
Vested fair value	$ 27.2	$ 21.8	$ 11.5
Performance Shares
Nonvested RSUs and RSAs, Number of Shares
Nonvested at the beginning of the period (in shares)	92,481
Granted (in shares)	0
Vested (in shares)	(46,785)
Forfeited (in shares)	(31,049)
Nonvested at the end of the period (in shares)	14,647	92,481
Nonvested RSUs and RSAs, Weighted Average Grant Date Fair Value
Nonvested at the beginning of the period (in dollars per share)	$ 182.28
Granted (in dollars per share)	0
Vested (in dollars per share)	207.36
Forfeited (in dollars per share)	212.09
Nonvested at the end of the period (in dollars per share)	$ 210.55	$ 182.28
Unrecognized compensation cost	$ 2.8
Weighted-average period for recognition of unrecognized compensation cost	1 year 2 months 12 days
Vested fair value	$ 18.8	$ 7.9	$ 0.4
Minimum
Nonvested RSUs and RSAs, Weighted Average Grant Date Fair Value
Return performance, percent of target stock price		70.00%	70.00%
Minimum \| Performance Shares
Nonvested RSUs and RSAs, Weighted Average Grant Date Fair Value
Vesting period	6 months
Maximum \| Performance Shares
Nonvested RSUs and RSAs, Weighted Average Grant Date Fair Value
Vesting period	4 years