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Maximum percentage of exercise price at grand date fair value.

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Share-based Compensation Arrangement by Share-based Payment Award, Award Post-Vesting Holding Period

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Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Granted in Period, Fair Value

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Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Number of Persons Granted Shares

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Value of shares paid for employee tax withholding.

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Shares paid for employee tax withholding.

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Aggregate dividends paid during the period for each share of common stock outstanding.

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Aggregate dividends declared during the period for each share of common stock outstanding.

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Amount of paid and unpaid common stock dividends declared with the form of settlement in cash.

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The per share amount of a dividend declared, but not paid, as of the financial reporting date.

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Carrying value as of the balance sheet date of dividends declared but unpaid on equity securities issued by the entity and outstanding.

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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.

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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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Balance held at close of period in number of shares.

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Cash outflow in the form of capital distributions and dividends to common shareholders, preferred shareholders and noncontrolling interests.

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Cash received on stock transaction after deduction of issuance costs.

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The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

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Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

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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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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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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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Number of shares authorized for issuance under share-based payment arrangement.

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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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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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Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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Number of shares used to settle grantee's tax withholding obligation for award under share-based payment arrangement.

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Number of new stock issued during the period.

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Amount of stock repurchase plan authorized.

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Amount remaining of a stock repurchase plan authorized.

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Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern 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.

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STOCKHOLDERS' EQUITY AND EQUITY COMPENSATION (Details)							1 Months Ended	12 Months Ended
STOCKHOLDERS' EQUITY AND EQUITY COMPENSATION (Details)	Aug. 21, 2020 USD ($) $ / shares shares	Aug. 21, 2020 USD ($) $ / shares shares	Aug. 18, 2020 USD ($) $ / shares shares	Apr. 16, 2018 USD ($)	Mar. 07, 2018 USD ($) $ / shares	Jan. 29, 2016 shares	Aug. 31, 2020 USD ($) $ / shares shares	Sep. 30, 2020 USD ($) senior_executive $ / shares shares	Sep. 30, 2019 USD ($) $ / shares	Sep. 30, 2018 USD ($) $ / shares	Nov. 12, 2020 $ / shares	Jan. 30, 2020 shares	Aug. 01, 2018 USD ($)	Jun. 19, 2018 shares	Jan. 31, 2018 shares	Aug. 03, 2016 USD ($)	Dec. 31, 2008 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, dividends, per share, cash paid (in dollars per share) \| $ / shares								$ 0.30	$ 0.29	$ 0.28
Accrued dividends \| $								$ 3,535,000
Sale of stock, number of shares issued (in shares)	700,000	8,700,000	8,000,000				8,700,000
Sale of stock, stock price (in dollars per share) \| $ / shares	$ 21.50	$ 21.50	$ 21.50				$ 21.50
Net process from sale of stock \| $	$ 14,335,000	$ 178,165,000	$ 163,830,000				$ 178,165,000
Share-based payment award, number of shares authorized (in shares)								4,852,762
Share-based payment award, expiration period						10 years
Maximum percentage of exercise price at grant date fair value						100.00%
Share-based payment award, options, vested in period, fair value \| $								$ 17,889,000	$ 4,748,000	$ 11,216,000
Employee service share-based compensation, nonvested awards, compensation not yet recognized, share-based awards other than options \| $								$ 22,340,000
Employee service share-based compensation, nonvested awards, compensation cost not yet recognized, period for recognition								2 years 3 months 18 days
Stock repurchase program, authorized amount \| $													$ 50,000,000			$ 50,000,000
Stock repurchased during period (in shares)								0
Stock repurchase program, remaining authorized repurchase amount \| $								$ 57,955,000
Shares paid for tax withholding for share based compensation (in shares)								340,775
Shares paid for tax withholding for share based compensation, value \| $								$ 7,409,000
Shares paid for tax withholding for share based compensation, value per share (in dollars per share) \| $ / shares								$ 21.74
Common stock, number of shares held by shareholder														5,583,375
GS Direct
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Investment owned, balance (in shares)																	10,000,000
Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payment award, number of shares authorized (in shares)						5,050,000
Incentive Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock issued during period, shares, new issues (in shares)						600,000
Share-based payment award, number of shares available for grant (in shares)								1,167,172
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Instruments grants in period (in shares)								1,061,624
Weighted average grant date fair value (in dollars per share) \| $ / shares								$ 17.10
Instruments vested in period (in shares)								831,748
Shares paid for tax withholding for share based compensation (in shares)								3,307
Shares paid for tax withholding for share based compensation, value \| $								$ 70,000
Shares paid for tax withholding for share based compensation, value per share (in dollars per share) \| $ / shares								$ 21.22
Restricted Stock \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payment award, award vesting period								3 years
Restricted Stock \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payment award, award vesting period								4 years
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payment award, award vesting period								3 years
Instruments grants in period (in shares)								1,061,624
Instruments vested in period, fair value \| $								$ 7,446,000
Weighted average grant date fair value (in dollars per share) \| $ / shares								$ 21.38
Restricted Stock and Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Instruments grants in period (in shares)								348,280
Director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payment award, award vesting period								3 years
Instruments grants in period (in shares)								53,344
Instruments vested in period, fair value \| $								$ 1,170,000
Weighted average grant date fair value (in dollars per share) \| $ / shares								$ 21.93
Executive Officer \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payment award, award vesting period								4 years
Instruments number of persons granted shares (in shares) \| senior_executive								2
Post-vesting holding period								2 years
Executive Officer \| Restricted Stock \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Instruments vested in period (in shares)								480,000
Executive Officer \| Restricted Stock \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Instruments vested in period (in shares)								660,000
Executive Officer \| Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant date fair value (in dollars per share) \| $ / shares								$ 14.45
Equity instruments other than options, granted in period, fair value \| $								$ 9,534,000
Executive Officer \| Restricted Stock and Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Instruments grants in period (in shares)								660,000
Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payment award, number of shares authorized (in shares)												1,700,000			1,000,000
Special Dividends
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, dividends declared (in dollars per share) \| $ / shares					$ 1.00
Dividends, common stock, cash \| $					$ 38,073,000
Payments of dividends \| $				$ 38,073,000
Subsequent Event
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dividends payable, amount per share (in dollars per share) \| $ / shares											$ 0.08