EMPLOYEE BENEFIT PLANS	12 Months Ended
EMPLOYEE BENEFIT PLANS	Sep. 30, 2017
Compensation Related Costs [Abstract]
EMPLOYEE BENEFIT PLANS	EMPLOYEE BENEFIT PLANS: The Company offers a retirement savings plan for its employees under Section 401(k) and Section 401(a) of the Internal Revenue Code (the “Mohegan Retirement and 401(k) Plan”). Under the 401(k) portion of the plan, participants may contribute between 1% and 25% of eligible compensation up to the maximum allowed by the Internal Revenue Code. The Company may make discretionary matching contributions of 50%, up to the first 3% of participants’ eligible compensation contributed to the 401(k) portion of the plan. In general, employees become eligible for the Mohegan Retirement and 401(k) Plan after 90 days of service and become fully vested after five years of service. Under the retirement portion of the plan, the Company may make discretionary retirement contributions based on a rate of $0.30 per qualified hour worked. Discretionary retirement contributions have been suspended since February 2009. The Company contributed $2.6 million, $2.3 million and $2.2 million, net of forfeitures, to the Mohegan Retirement and 401(k) Plan for the fiscal years ended September 30, 2017, 2016 and 2015, respectively. The Company, together with the Tribe, also offers a non-qualified deferred compensation plan for certain key employees (the “Mohegan Deferred Compensation Plan”). Under the Mohegan Deferred Compensation Plan, participants may defer up to 100% of their compensation. The total balance under the Mohegan Deferred Compensation Plan increased by $2.1 million for the fiscal year ended September 30, 2017. The total balance under the Mohegan Deferred Compensation Plan declined by $3.1 million and $942,000 for the fiscal years ended September 30, 2016 and 2015, respectively. In fiscal 2016, the Company, together with the Tribe, began offering the Mohegan Benefit Plan. The Mohegan Benefit Plan is sponsored by the Tribe for the benefit of participants who authorize the purchase of life insurance policies as a means of providing certain life insurance benefits to the participants and their spouses as joint insured. The life insurance policies are established on the life of each participant, and each premium contribution provided by the Company to the Tribe on behalf of the participant is treated as a loan from the Company to the Tribe and, in turn, as a loan from the Tribe to the participant, for legal, tax and financial reporting purposes. The loans from the Company to the Tribe are recorded as a long-term loan receivable due from the Tribe. This loan receivable is required to be repaid by the Tribe. Accordingly, the Tribe retains an interest in each participant’s death benefit from the life insurance policies that will provide the Company with full repayment of the accumulated loan receivable at the death of the applicable participants insured under the life insurance policies. Participant contributions under the Mohegan Benefit Plan totaled $1.9 million and $1.4 million for the fiscal years ended September 30, 2017 and 2016, respectively.

The entire disclosure for compensation costs, including compensated absences accruals, compensated absences liability, deferred compensation arrangements and income statement compensation items. Deferred compensation arrangements may include a description of an arrangement with an individual employee, which is generally an employment contract between the entity and a selected officer or key employee containing a promise by the employer to pay certain amounts at designated future dates, usually including a period after retirement, upon compliance with stipulated requirements. This type of arrangement is distinguished from broader based employee benefit plans as it is usually tailored to the employee. Disclosure also typically includes the amount of related compensation expense recognized during the reporting period, the number of shares (units) issued during the period under such arrangements, and the carrying amount as of the balance sheet date of the related liability.