OTHER CURRENT ASSETS AND OTHER CURRENT LIABILITIES (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013
Other Assets, Current [Abstract]
Non-qualified deferred compensation	$ 9,809	$ 9,832
Prepaid expenses and other miscellaneous current assets	7,188us-gaap_PrepaidExpenseCurrent	10,686us-gaap_PrepaidExpenseCurrent
Total other current assets	16,997us-gaap_OtherAssetsCurrent	20,518us-gaap_OtherAssetsCurrent
Other Liabilities, Current [Abstract]
Accrued payroll and related taxes and benefits	35,602	36,538
Combined outstanding Slot Win Contribution and free promotional slot play contribution	11,617	12,691
Accrued severance	771	2,395
Amounts due to horsemen	8,109mtga_AmountsDueToHorsemenCurrent	7,805mtga_AmountsDueToHorsemenCurrent
Other miscellaneous current liabilities	71,076us-gaap_OtherAccruedLiabilitiesCurrent	64,553us-gaap_OtherAccruedLiabilitiesCurrent
Total other current liabilities	$ 127,175us-gaap_OtherLiabilitiesCurrent	$ 123,982us-gaap_OtherLiabilitiesCurrent

Accrued Payroll and Related Taxes and Benefits, Current

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Amounts Due to Horsemen, Current

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- Definition

Combined Outstanding Slot Win Contribution and Free Promotional Slot Play Contribution, Current

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Aggregate carrying value as of the balance sheet date of the liabilities for deferred compensation arrangements payable within one year (or the normal operating cycle, if longer). Represents currently earned compensation under cash arrangements (such as a profit-sharing plan, rabbi trust, and employee contract--excluding equity-based arrangements) that is not actually paid until a later date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 710

-SubTopic 10

-Section 30

-Paragraph 2

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Carrying value as of the balance sheet date of obligations incurred through that date and payable arising from transactions not otherwise specified in the taxonomy. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

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-Glossary Current Liabilities

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Aggregate carrying amount, as of the balance sheet date, of current assets not separately disclosed in the balance sheet. Current assets are expected to be realized or consumed within one year (or the normal operating cycle, if longer).

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Aggregate carrying amount of current liabilities (due within one year or within the normal operating cycle if longer) not separately disclosed in the balance sheet. Includes costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered and of liabilities not separately disclosed.

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- Definition

For a classified balance sheet, the carrying amount as of the balance sheet date of the portion of the obligations recognized for the various benefits provided to former or inactive employees, their beneficiaries, and covered dependents after employment but before retirement that is payable within one year of the balance sheet date.

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Amount of asset related to consideration paid in advance for costs that provide economic benefits within a future period of one year or the normal operating cycle, if longer.

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