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STOCKHOLDERS' EQUITY AND EQUITY COMPENSATION (Details) |  |  |  |  | 12 Months Ended | 49 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Jan. 30, 2014 shares | Jan. 10, 2014 USD ($) installment $ / shares shares | Dec. 10, 2013 USD ($) $ / shares shares | Nov. 12, 2013 | Sep. 30, 2015 USD ($) $ / shares shares | Sep. 30, 2014 USD ($) $ / shares shares | Sep. 30, 2013 USD ($) $ / shares shares | Sep. 30, 2015 USD ($) $ / shares shares | Jul. 31, 2015 USD ($) | Mar. 31, 2015 USD ($) | May. 31, 2014 USD ($) | Aug. 31, 2011 USD ($)
STOCKHOLDERS' EQUITY AND EQUITY COMPENSATION (Details) [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Common stock, dividends, per share, cash paid (in Dollars per share) | $ / shares |  |  |  |  | $ 0.16 | $ 0.12 | $ 0.10 |  |  |  |  |
Share-based payment award, description |  |  |  |  | Options granted under the Incentive Plan may be either “incentive stock options” or nonqualified stock options, generally expire ten years after the date of grant and are granted at an exercise price of not less than 100% of the fair market value at the date of grant. |  |  |  |  |  |  |
Share-based payment award, expiration period | 10 years |  |  |  |  |  |  |  |  |  |  |
Maximum percentage of exercise price at grant date fair value | 100.00% |  |  |  |  |  |  |  |  |  |  |
Share-based payment award, number of shares authorized (in Shares) |  |  |  |  | 4,245,700 |  |  | 4,245,700 |  |  |  |
Share-based payment award, options, vested in period, fair value | $ |  |  |  |  | $ 5,068,000 | $ 14,058,000 | $ 13,270,000 |  |  |  |  |
Employee service share-based compensation, nonvested awards, compensation not yet recognized, share-based awards other than options | $ |  |  |  |  | $ 13,054,000 |  |  | $ 13,054,000 |  |  |  |
Employee service share-based compensation, nonvested awards, compensation cost not yet recognized, period for recognition |  |  |  |  | 1 year 7 months |  |  |  |  |  |  |
Stock repurchased during period, shares (in Shares) |  |  | 4,444,444 |  | 5,311,915 | 1,906,631 | 2,369,786 | 16,751,221 |  |  |  |
Stock repurchased during period, value | $ |  |  | $ 50,000,000 |  | $ 80,934,000 | $ 23,167,000 | $ 26,285,000 | $ 203,132,000 |  |  |  |
Stock repurchased during period per share (in Dollars per share) | $ / shares |  |  | $ 11.25 |  | $ 15.24 | $ 12.15 | $ 11.09 | $ 12.13 |  |  |  |
Repurchased on the open market, shares |  |  |  |  | 12,306,777 |  |  |  |  |  |  |
Stock repurchased during period, share price discount rate |  |  |  | 9.20% |  |  |  |  |  |  |  |
Stock repurchase program, authorized amount | $ |  |  | $ 50,000,000 |  |  | $ 20,000,000 |  |  | $ 50,000,000 | $ 50,000,000 | $ 50,000,000 | $ 50,000,000
Stock issued during period, value, ESOP | $ |  |  |  |  |  | $ 20,000,000 |  |  |  |  |  |
Stock issued during period, shares, ESOP |  |  |  |  |  | 1,591,117 |  |  |  |  |  |
ESOP, weighted average purchase price of shares purchased (in Dollars per share) | $ / shares |  |  |  |  |  | $ 12.57 |  |  |  |  |  |
Stock repurchase program, remaining authorized repurchase amount | $ |  |  |  |  | $ 57,926,000 |  |  | $ 57,926,000 |  |  |  |
Shares paid for tax withholding for share based compensation (in Shares) |  |  |  |  | 89,488 |  |  |  |  |  |  |
Shares paid for tax withholding for share based compensation, value | $ |  |  |  |  | $ 1,409,000 |  |  |  |  |  |  |
Shares paid for tax withholding for share based compensation, value per share (in Dollars per share) | $ / shares |  |  |  |  | $ 15.74 |  |  |  |  |  |  |
Northcote Holdings Pty. Ltd [Member] |  |  |  |  |  |  |  |  |  |  |  |
STOCKHOLDERS' EQUITY AND EQUITY COMPENSATION (Details) [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Stock issued during period, shares, acquisitions |  | 44,476 |  |  |  |  |  |  |  |  |  |
Stock issued during period, value, acquisitions | $ |  | $ 584,000 |  |  |  |  |  |  |  |  |  |
Business acquisition, share price (in Dollars per share) | $ / shares |  | $ 13.13 |  |  |  |  |  |  |  |  |  |
GS Direct [Member] |  |  |  |  |  |  |  |  |  |  |  |
STOCKHOLDERS' EQUITY AND EQUITY COMPENSATION (Details) [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Shares, outstanding |  |  | 5,560,000 |  |  |  |  |  |  |  |  |
Percentage held common stock outstanding |  |  | 10.00% |  |  |  |  |  |  |  |  |
Incentive Plan [Member] |  |  |  |  |  |  |  |  |  |  |  |
STOCKHOLDERS' EQUITY AND EQUITY COMPENSATION (Details) [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Share-based payment award, number of additional shares authorized | 1,200,000 |  |  |  |  |  |  |  |  |  |  |
Share-based payment award, number of shares authorized (in Shares) | 4,200,000 |  |  |  |  |  |  |  |  |  |  |
Incentive Stock Options [Member] |  |  |  |  |  |  |  |  |  |  |  |
STOCKHOLDERS' EQUITY AND EQUITY COMPENSATION (Details) [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) |  |  |  |  | 420,206 |  |  | 420,206 |  |  |  |
2006 Equity Incentive Plan [Member] |  |  |  |  |  |  |  |  |  |  |  |
STOCKHOLDERS' EQUITY AND EQUITY COMPENSATION (Details) [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Share based payment award equity instruments other than options additional grants in future (in Shares) |  |  |  |  | 0 |  |  | 0 |  |  |  |
Restricted Stock [Member] |  |  |  |  |  |  |  |  |  |  |  |
STOCKHOLDERS' EQUITY AND EQUITY COMPENSATION (Details) [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Share-based payment award, award vesting period |  |  |  |  | 3 years |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period |  |  |  |  | 687,506 |  |  |  |  |  |  |
Weighted average grant date fair value (in Dollars per share) | $ / shares |  |  |  |  | $ 13.05 |  |  |  |  |  |  |
Restricted Stock [Member] | Northcote Holdings Pty. Ltd [Member] |  |  |  |  |  |  |  |  |  |  |  |
STOCKHOLDERS' EQUITY AND EQUITY COMPENSATION (Details) [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Share-based payment award, award vesting period |  | 3 years |  |  |  |  |  |  |  |  |  |
Share-based payment award, non-option equity instruments, granted (in Shares) |  | 1 |  |  |  |  |  |  |  |  |  |
Number of installments for vesting of stock awards | installment |  | 3 |  |  |  |  |  |  |  |  |  |
Restricted Stock [Member] | Minimum [Member] |  |  |  |  |  |  |  |  |  |  |  |
STOCKHOLDERS' EQUITY AND EQUITY COMPENSATION (Details) [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Share-based payment award, award vesting period |  |  |  |  | 3 years |  |  |  |  |  |  |
Restricted Stock [Member] | Maximum [Member] |  |  |  |  |  |  |  |  |  |  |  |
STOCKHOLDERS' EQUITY AND EQUITY COMPENSATION (Details) [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Share-based payment award, award vesting period |  |  |  |  | 4 years |  |  |  |  |  |  |
Performance Shares [Member] |  |  |  |  |  |  |  |  |  |  |  |
STOCKHOLDERS' EQUITY AND EQUITY COMPENSATION (Details) [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Grant Date Fair Value | $ |  |  |  |  | $ 7,706,000 |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period |  |  |  |  | 604,715 |  |  |  |  |  |  |
Weighted average grant date fair value (in Dollars per share) | $ / shares |  |  |  |  | $ 12.74 |  |  |  |  |  |  |

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- Definition General descriptive information regarding an arrangement under which employees and directors receive: (a) awards of equity shares, equity share options, or other equity instruments; or (b) the entity incurs liabilities to them: (1) in amounts based, at least in part, on the price of the entity's shares or other equity instruments; or (2) that require or may require settlement by issuance of the entity's shares. Such an arrangement is usually provided to employees and directors to compensate them, provide performance incentives to them, and to attract or retain their services. May also include pertinent information particular to a plan that is not elsewhere specified in the taxonomy. + 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) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901 + Details
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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). + 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)(3) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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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 + Details
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