Accrued Interest Payable, Including Commitment Fees

No definition available.

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- Definition

Debt Instrument, Amortization Of Principal, Percentage, Annual

+ References

No definition available.

+ Details

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- Definition

Debt Instrument, Amortization Of Principal, Percentage, Year One

+ References

No definition available.

+ Details

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Namespace Prefix:	mtga_
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- Definition

Debt Instrument, Amortization Of Principal, Percentage, Year Three

+ References

No definition available.

+ Details

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Namespace Prefix:	mtga_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Debt Instrument, Amortization Of Principal, Percentage, Year Two

+ References

No definition available.

+ Details

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Namespace Prefix:	mtga_
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Period Type:	instant

- Definition

Debt Instrument, Exit Fee

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

Debt Instrument, Interest Rate, Stated Percentage, Due At Maturity

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Debt Instrument, Interest Rate, Stated Percentage, Due Monthly

+ References

No definition available.

+ Details

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Namespace Prefix:	mtga_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Debt Instrument, Variable Rate at Period End

+ References

No definition available.

+ Details

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Namespace Prefix:	mtga_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Debt Instrument, Variable Rate Basis, Minimum

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Debt Instrument, Variable Rate, Leverage-based Margin

+ References

No definition available.

+ Details

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Namespace Prefix:	mtga_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Debt Instrument, Variable Rate, Measurement Period

+ References

No definition available.

+ Details

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- Definition

Long-term Debt, Including Due to Related Parties

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Long-term Debt, Including Due to Related Parties, Excluding Deferred Income, Gain on Sale of Derivatives, Net

+ References

No definition available.

+ Details

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Namespace Prefix:	mtga_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 55

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=34725769&loc=d3e28878-108400

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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- Details

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- Definition

Carrying value as of the balance sheet date of [accrued] interest payable on all forms of debt, including trade payables, that has been incurred and is unpaid. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 20

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Current Liabilities

-URI http://asc.fasb.org/extlink&oid=6509677

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section 45

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=28358313&loc=d3e6935-107765

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.20)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section 45

-Paragraph 9

-URI http://asc.fasb.org/extlink&oid=28358313&loc=d3e7018-107765

+ Details

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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.16)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 20, 22

-Article 5

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.16)

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

+ Details

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19(b),22(b))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

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- Details

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LONG-TERM DEBT - Credit Facilities (Details) (USD $)	1 Months Ended	12 Months Ended
LONG-TERM DEBT - Credit Facilities (Details) (USD $)	Nov. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Mar. 31, 2012	Jul. 31, 2012
Debt Instrument [Line Items]
Accrued interest		$ 8,659,000us-gaap_InterestPayableCurrent	$ 23,296,000us-gaap_InterestPayableCurrent
Long-term debt, including due to related parties		1,730,936,000	1,682,312,000
Credit Facility \| Bank Credit Facility
Debt Instrument [Line Items]
Credit facility outstanding				400,000,000.0
Accrued interest			61,000
Long-term debt, including due to related parties		0	393,000,000
Credit Facility \| Term Loan Credit Facility
Debt Instrument [Line Items]
Loan face amount				225,000,000.0
Accrued interest			1,100,000
Long-term debt, including due to related parties		0	221,995,000
Credit Facility \| Senior Secured Credit Facilities
Debt Instrument [Line Items]
Loan face amount	955,000,000.0
Accrued interest payable, including commitment fees		212,000
Credit Facility \| Senior Secured Credit Facility - Revolving
Debt Instrument [Line Items]
Loan face amount	100,000,000
Credit facility outstanding		0
Debt outstanding		37,000,000
Letters of credit issued		2,900,000
Remaining borrowing capacity		57,100,000
Long-term debt, including due to related parties		37,000,000	0
Credit Facility \| Senior Secured Credit Facility - Revolving \| Minimum
Debt Instrument [Line Items]
Fee assessed on unused revolving credit	0.375%
Credit Facility \| Senior Secured Credit Facility - Revolving \| Maximum
Debt Instrument [Line Items]
Fee assessed on unused revolving credit	0.50%
Credit Facility \| Senior Secured Credit Facility - Revolving \| LIBOR \| Minimum
Debt Instrument [Line Items]
Variable rate, leverage-based margin	3.50%
Credit Facility \| Senior Secured Credit Facility - Revolving \| LIBOR \| Maximum
Debt Instrument [Line Items]
Variable rate, leverage-based margin	4.50%
Credit Facility \| Senior Secured Credit Facility - Revolving \| Base Rate
Debt Instrument [Line Items]
Long-term debt, including due to related parties		14,000,000
Debt instrument, variable rate at period end		3.25%
Basis spread on variable rate		3.50%
Credit Facility \| Senior Secured Credit Facility - Revolving \| Base Rate \| Minimum
Debt Instrument [Line Items]
Variable rate, leverage-based margin	2.50%
Credit Facility \| Senior Secured Credit Facility - Revolving \| Base Rate \| Maximum
Debt Instrument [Line Items]
Variable rate, leverage-based margin	3.50%
Credit Facility \| Senior Secured Credit Facility - Revolving \| Eurodollar
Debt Instrument [Line Items]
Long-term debt, including due to related parties		23,000,000
Debt instrument, variable rate at period end		0.15%
Basis spread on variable rate		4.50%
Credit Facility \| Senior Secured Credit Facility - Revolving \| One-Month London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Basis spread on variable rate	1.00%
Credit Facility \| Senior Secured Credit Facility - Revolving \| Federal Funds Effective Swap Rate
Debt Instrument [Line Items]
Basis spread on variable rate	0.50%
Credit Facility \| Senior Secured Credit Facility - Term Loan A
Debt Instrument [Line Items]
Loan face amount	125,000,000
Interest rate, year one	5.00%
Interest rate, year two	7.50%
Interest rate, year three	10.00%
Debt outstanding		120,300,000
Long-term debt, including due to related parties		119,789,000	0
Credit Facility \| Senior Secured Credit Facility - Term Loan A \| LIBOR \| Minimum
Debt Instrument [Line Items]
Variable rate, leverage-based margin	3.50%
Credit Facility \| Senior Secured Credit Facility - Term Loan A \| LIBOR \| Maximum
Debt Instrument [Line Items]
Variable rate, leverage-based margin	4.50%
Credit Facility \| Senior Secured Credit Facility - Term Loan A \| Base Rate \| Minimum
Debt Instrument [Line Items]
Variable rate, leverage-based margin	2.50%
Credit Facility \| Senior Secured Credit Facility - Term Loan A \| Base Rate \| Maximum
Debt Instrument [Line Items]
Variable rate, leverage-based margin	3.50%
Credit Facility \| Senior Secured Credit Facility - Term Loan A \| Eurodollar
Debt Instrument [Line Items]
Debt instrument, variable rate at period end		0.23%
Basis spread on variable rate		4.50%
Credit Facility \| Senior Secured Credit Facility - Term Loan A \| One-Month London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Basis spread on variable rate	1.00%
Credit Facility \| Senior Secured Credit Facility - Term Loan A \| Federal Funds Effective Swap Rate
Debt Instrument [Line Items]
Basis spread on variable rate	0.50%
Credit Facility \| Senior Secured Credit Facility - Term Loan B
Debt Instrument [Line Items]
Loan face amount	730,000,000
Amortization of principal, percentage, annual	1.00%
Debt outstanding		724,500,000
Long-term debt, including due to related parties		716,188,000	0
Credit Facility \| Senior Secured Credit Facility - Term Loan B \| LIBOR
Debt Instrument [Line Items]
Variable rate, minimum	1.00%
Basis spread on variable rate	4.50%
Credit Facility \| Senior Secured Credit Facility - Term Loan B \| Base Rate
Debt Instrument [Line Items]
Variable rate, minimum	2.00%
Basis spread on variable rate	3.50%
Credit Facility \| Senior Secured Credit Facility - Term Loan B \| Eurodollar
Debt Instrument [Line Items]
Debt instrument, variable rate at period end		1.00%
Basis spread on variable rate		4.50%
Credit Facility \| Bank of America, N.A. Line of Credit
Debt Instrument [Line Items]
Credit facility outstanding		3,000,000
Borrowing capacity	16,500,000.0
Accrued interest		23,000	0
Long-term debt, including due to related parties		3,041,000	0
Credit Facility \| Downs Lodging Credit Facility
Debt Instrument [Line Items]
Long-term debt, including due to related parties		45,000,000	45,000,000
Credit Facility \| Downs Lodging Credit Facility \| Downs Lodging, LLC
Debt Instrument [Line Items]
Loan face amount					45,000,000.0
Accrued interest		0	0
Note stated interest rate					13.00%
Interest rate due monthly					10.00%
Interest rate due at maturity					3.00%
Exit fee					3.00%
Credit Facility \| Letter of Credit \| Bank Credit Facility
Debt Instrument [Line Items]
Borrowing capacity				$ 75,000,000.0
Credit Facility \| Term Loan A Facility \| Senior Secured Credit Facilities \| LIBOR
Debt Instrument [Line Items]
Variable rate, measurement period	1 month
Credit Facility \| Revolving Credit Facility \| Senior Secured Credit Facility - Revolving
Debt Instrument [Line Items]
Fee assessed on unused revolving credit		0.50%