STOCK-BASED COMPENSATION (Details) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares of common stock that may be issued (in shares)	1,250,000
Stock Option Awards [Abstract]
Employees’ taxes paid associated with restricted shares withheld upon vesting	$ (1.1)	$ (0.9)	$ (1.2)
Closing price of common stock (in dollars per share)	$ 46.40
Total unrecognized compensation costs	7.0
Weighted average period for recognition of unrecognized compensation costs	2 years
Restricted Stock Awards
Restricted Stock Awards [Abstract]
Vested (in shares)	88,533	91,221	90,839
Vested restricted stock withheld for tax withholding obligations (in shares)	23,776	23,311	30,052
Vested restricted stock withheld for tax withholding obligations, weighted average price (in dollars per share)	$ 45.96	$ 39.96	$ 40.02
Fair value, restricted stock	4.1	3.8	4.2
Actual tax benefit realized	1.6	1.4	1.6
Stock Option Awards
Stock Option Awards [Abstract]
Exercise price range , minimum (in dollars per share)	$ 30.46
Exercise price range , maximum (in dollars per share)	$ 34.95
Cash received from the exercise of stock options	1.7	2.7	2.5
Intrinsic value of exercised	0.9	1.0	1.0
Employees’ taxes paid associated with restricted shares withheld upon vesting	$ 0.3	$ 0.4	$ 0.4
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period, minimum	3 years
Performance Vesting \| Restricted Stock Awards
Restricted Stock Awards [Abstract]
Granted (in shares)	125,727
Granted, weighted average grant date fair value (per share)	$ 37.21
Vested (in shares)	52,954
Time Vesting \| Restricted Stock Awards
Restricted Stock Awards [Abstract]
Granted (in shares)	76,568
Granted, weighted average grant date fair value (per share)	$ 45.74
Vested (in shares)	35,579
Executive Officers and Key Employees \| Performance Vesting \| Restricted Stock Awards
Restricted Stock Awards [Abstract]
Granted, weighted average grant date fair value (per share)		$ 34.49	$ 36.55
Executive Officers and Key Employees \| Time Vesting \| Restricted Stock Awards
Restricted Stock Awards [Abstract]
Granted (in shares)	59,468
Granted, weighted average grant date fair value (per share)	$ 45.66	$ 40.03	$ 39.72
Non Employee Directors \| Time Vesting \| Restricted Stock Awards
Restricted Stock Awards [Abstract]
Granted (in shares)	17,100
Granted, weighted average grant date fair value (per share)	$ 46.02	$ 39.92	$ 41.36

Disclosure of the aggregate tax benefit realized from the exercise of equity instruments during the annual period.

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This element represents the number of vested shares withheld pursuant to elections by employees to satisfy tax withholding obligations.

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The weighted-average price of vested compensation awards withheld to satisfy tax withholding obligations.

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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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Unrecognized cost of unvested share-based compensation awards.

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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.

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

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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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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).

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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).

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

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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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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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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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The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

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The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

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Price of a single share of a number of saleable stocks of a company.

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