Number of performance periods for which market-based restricted stock will be measured for vesting purposes

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- Definition

Performance-based restricted stock awards granted

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No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Potential Performance Award Percentage

+ References

No definition available.

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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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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://www.xbrl.org/2003/role/presentationRef
-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=96867065&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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-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=96867065&loc=d3e5070-113901

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=96867065&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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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

+ References

No definition available.

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- Definition

Weighted average remaining contractual term of outstanding stock options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (e)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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SHARE-BASED COMPENSATION PLANS (Details Textual) $ / shares in Units, $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2018 USD ($) award $ / shares shares	Mar. 31, 2017 $ / shares shares	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding options, term	10 years
Performance-based restricted stock awards granted (in shares)	98,000	79,000
Number of performance periods for which market-based restricted stock will be measured for vesting purposes \| award	3
Award vesting period	1 year
Compensation cost not yet recognized \| $	$ 44
Compensation cost not yet recognized, period for recognition	3 years
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Potential performance award percentage	200.00%
ROC/COC Performance Based Restricted Stock Rights
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants in period (in shares)	51,000
Grants in period, weighted average grant date fair value (in dollars per share) \| $ / shares	$ 72.93
Equity Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options granted (in shares)	347,000	462,000
Options, grants in period, weighted average exercise price (in dollars per share) \| $ / shares	$ 15.89	$ 15.71
Award vesting period	3 years
Market Based Restricted Stock Rights
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants in period (in shares)	0	45,000
Grants in period, weighted average grant date fair value (in dollars per share) \| $ / shares		$ 73.43
Performance Based Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants in period (in shares)	95,000	142,000
Grants in period, weighted average grant date fair value (in dollars per share) \| $ / shares	$ 74.72	$ 76.49
SRG Performance Based Restricted Stock Rights
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants in period (in shares)	51,000
Grants in period, weighted average grant date fair value (in dollars per share) \| $ / shares	$ 72.93
Time Vested Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants in period (in shares)	132,000	85,000
Grants in period, weighted average grant date fair value (in dollars per share) \| $ / shares	$ 76.69	$ 76.57
Award vesting period	3 years
Vested awards	104,000
Market Based Restricted Stock Rights, 2012 Grant \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Potential performance award percentage			150.00%
ROC performance based restricted stock rights, 2013 Grant \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Potential performance award percentage	150.00%	150.00%
Year One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	1 year
Year Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	2 years
Year Three
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	3 years