SHAREHOLDERS' EQUITY AND EMPLOYEE BENEFIT PLANS (Narrative) (Details) - USD ($) shares in Millions, $ in Millions	3 Months Ended	6 Months Ended
Mar. 31, 2018	Mar. 31, 2018	Aug. 15, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Description Of Maximum Percentage Of Employee Contributions and Matching Contributions Based Upon Years Of Service		employee contributions and matching Company contributions from 4% to 6%
Stock Repurchase Program, Authorized Amount			$ 100.0
Shares repurchased in period (shares)	0.9	1.0
Shares repurchased in period	$ 21.5	$ 24.8
Remaining repurchase authorized amount	$ 64.0	$ 64.0
Relative Total Shareholder Return Average Stock Price Calculation Period		90 days
Total Shareholder Return Award Performance Measurement Period		3 years
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay		4.00%
Share Based Compensation Arrangement By Share Based Payment Award Vesting Percentage	0.00%	0.00%
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay		6.00%
Share Based Compensation Arrangement By Share Based Payment Award Vesting Percentage	200.00%	200.00%
Equity Incentive Plan 2017 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	4.7	4.7

Defined benefit plan employer contribution percentage match of compensation.

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The relative total shareholders' return average stock price calculation period

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- Definition

Share based compensation arrangement by share based payment award options vesting period.

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- Definition

The share based compensation arrangement by share based payment award vesting percentage reported.

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- Definition

Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

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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.

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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Amount of stock repurchase plan authorized.

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- Definition

Amount remaining of a stock repurchase plan authorized.

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- Definition

Equity impact of the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Publisher FASB
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Number of shares that have been repurchased during the period and are being held in treasury.

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