The number of share-based compensation plans approved by the entity's shareholders.

No definition available.

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Description of award terms as to how many shares or portion of an award are no longer contingent on satisfaction of either a service condition, market condition or a performance condition, thereby giving the employee the legal right to convert the award to shares, shown as a percentage of the original share amount.

+ References

No definition available.

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 14
-Section F

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- Definition

Aggregate proceeds received by the entity during the annual period from exercises of stock or unit options and conversion of similar instruments granted under equity-based payment arrangements.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Unrecognized cost of unvested share-based compensation awards.

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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Disclosure of the aggregate tax benefit realized from the exercise of stock options and the conversion of similar instruments during the annual period.

+ 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.

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-Publisher FASB
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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
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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

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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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.

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- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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-Publisher FASB
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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Intrinsic value of equity-based compensation awards outstanding. Excludes stock and unit options.

+ References

No definition available.

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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.

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STOCK-BASED COMPENSATION PLANS (Details) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2015 USD ($) plan $ / shares shares	Dec. 31, 2014 USD ($) $ / shares	Dec. 31, 2013 USD ($) $ / shares
Share-based Compensation Arrangement by Share-based Payment Award
Number of stock-based employee compensation plans \| plan	2
Non-cash stock-based compensation expense	$ 6,300	$ 5,900	$ 7,800
Total unrecognized compensation cost related to non-vested stock awards	$ 11,600
Weighted average period over which compensation cost is expected to be recognized	1 year 4 months 6 days
Intrinsic value of stock based awards other than options	$ 6,000
2015 Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award
Number of shares authorized for issuance \| shares	11,500,000.0
Number of shares available for grant \| shares	8,400,000
Minimum
Share-based Compensation Arrangement by Share-based Payment Award
Expiration period	7 years
Vesting period	4 years
Maximum
Share-based Compensation Arrangement by Share-based Payment Award
Expiration period	10 years
Vesting period	5 years
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award
Total amount of cash received from the exercise of options	$ 1,700	22,200	14,600
Tax benefit associated with the exercise of awards	600	3,700	15,400
Exercised	$ 1,970	$ 13,900	$ 44,600
Options, grants in period, weighted average grant date fair value (in dollars per share) \| $ / shares	$ 15.64	$ 11.08	$ 16.16
Time Vesting Restricted Stock Awards \| 2015 Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award
Vesting period	3 years
Weighted average grant date fair value (in dollars per share) \| $ / shares	$ 47.85	43.38	50.39
Performance Vesting Restricted Stock Awards
Share-based Compensation Arrangement by Share-based Payment Award
Vesting period	3 years
Performance Vesting Restricted Stock Awards \| 2015 Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award
Weighted average grant date fair value (in dollars per share) \| $ / shares	$ 49.00	$ 44.62	$ 45.76
Performance Vesting Restricted Stock Awards \| Minimum \| 2015 Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award
Vesting rights percentage	0.00%
Performance Vesting Restricted Stock Awards \| Maximum \| 2015 Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award
Vesting rights percentage	200.00%
Restricted Stock Awards
Share-based Compensation Arrangement by Share-based Payment Award
Intrinsic value of stock based awards other than options		$ 4,400
Restricted Stock Awards \| 2015 Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award
Intrinsic value of stock based awards other than options	$ 2,400	$ 4,300	$ 3,800