Debt instrument maturity.

No definition available.

Name:	mgm_DebtInstrumentMaturity
Namespace Prefix:	mgm_
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Balance Type:	na
Period Type:	duration

- Definition

Debt instrument maturity year.

+ References

No definition available.

+ Details

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- Definition

Fair value of interest rate swaps not qualified as cash flow hedges recorded as liability.

+ References

No definition available.

+ Details

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- Definition

Fair value of interest rate swaps qualified as cash flow hedges recorded as asset.

+ References

No definition available.

+ Details

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- Definition

Fair value of interest rate swaps qualified as cash flow hedges recorded as liability.

+ References

No definition available.

+ Details

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- Definition

Amount of cash eligible for distribution to members or limited partners of limited liability company (LLC) or limited partnership (LP), subject to reserves to be maintained as defined in operating or partnership agreement, or in a credit facility agreement.

+ References

No definition available.

+ Details

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

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+ Details

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

- Definition

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

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+ Details

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

- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

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Balance Type:	na
Period Type:	instant

- Definition

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

+ References

+ Details

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

- Definition

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.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Face (par) amount of the original debt instrument that was repurchased.

+ References

No definition available.

+ Details

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

- Definition

Average fixed interest rate related to the group of interest rate derivatives.

+ References

No definition available.

+ Details

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

- Definition

Nominal or face amount used to calculate payment on derivative.

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Balance Type:	na
Period Type:	instant

- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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

- 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.

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+ Details

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

- 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

+ Details

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

- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ 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 cash outflow to repay long-term debt that is wholly or partially secured by collateral. Excludes repayments of tax exempt secured debt.

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-Publisher FASB
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-Subparagraph (b)
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Balance Type:	credit
Period Type:	duration

- Definition

The cash outflow for a long-term debt where the holder has highest claim on the entity's asset in case of bankruptcy or liquidation during the period.

+ References

+ Details

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Period Type:	duration

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Long-Term Debt - Additional Information (Detail) - USD ($)			1 Months Ended		3 Months Ended		12 Months Ended
	Apr. 23, 2020	Feb. 14, 2020	Mar. 31, 2020	Feb. 29, 2020	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019	Apr. 30, 2020
Debt Instrument [Line Items]
Repayment and termination of existing revolving facility					$ 846,724,000	$ 850,000,000
Loss on early retirement of debt					(126,743,000)	$ 0
Credit facility amount			$ 11,815,242,000		11,815,242,000		$ 11,271,706,000
Fair value of interest rate swaps qualified as cash flow hedges recorded as liability			117,000,000		117,000,000		28,000,000
Fair value of interest rate swaps qualified as cash flow hedges recorded as asset			7,000,000		7,000,000
Fair value of interest rate swaps not qualified as cash flow hedges recorded as liability			15,000,000		15,000,000		3,000,000
Long-term debt, fair value			11,100,000,000		11,100,000,000		$ 12,100,000,000
Term Loan B [Member] \| Interest Rate Swap [Member]
Debt Instrument [Line Items]
Notional amount			900,000		900,000
Term Loan B [Member] \| Interest Rate Swap [Member] \| Cash Flow Hedges [Member]
Debt Instrument [Line Items]
Notional amount			$ 1,900,000,000		$ 1,900,000,000
Weighted Average fixed interest rate			1.821%		1.821%
5.750% Senior Notes, Due 2025 [Member]
Debt Instrument [Line Items]
Long-term debt, interest rate (as a percent)			5.75%		5.75%
Long-term debt, maturity year			2025
4.625% senior notes, due 2026 [Member]
Debt Instrument [Line Items]
Long-term debt, interest rate (as a percent)			4.625%		4.625%		4.625%
Long-term debt, maturity year			2026		2026		2026
5.500% Senior Notes, Due 2027 [Member]
Debt Instrument [Line Items]
Long-term debt, interest rate (as a percent)			5.50%		5.50%
Long-term debt, maturity year			2027
Operating Partnership Senior Credit Facility [Member]
Debt Instrument [Line Items]
Loss on early retirement of debt				$ (18,000,000)
Operating Partnership Senior Credit Facility [Member] \| Term Loan B [Member]
Debt Instrument [Line Items]
Repayment of outstanding term loan facility				1,300,000,000
Operating Partnership Senior Credit Facility [Member] \| Term Loan A [Member]
Debt Instrument [Line Items]
Repayment of outstanding term loan facility				$ 399,000,000
Senior Notes [Member]
Debt Instrument [Line Items]
Loss on early retirement of debt			$ (105,000,000)
Subsequent Event [Member] \| 6.75% Senior Notes, Due 2025 [Member]
Debt Instrument [Line Items]
Long-term debt, principal amount	$ 750,000,000
Long-term debt, interest rate (as a percent)	6.75%
Long-term debt, maturity year	2025
Maximum [Member]
Debt Instrument [Line Items]
Long-term debt, aggregate principal amount of debt purchased			750,000,000		$ 750,000,000
Maximum [Member] \| 5.750% Senior Notes, Due 2025 [Member]
Debt Instrument [Line Items]
Long-term debt, aggregate principal amount of debt purchased			325,000,000		325,000,000
Maximum [Member] \| 4.625% senior notes, due 2026 [Member]
Debt Instrument [Line Items]
Long-term debt, aggregate principal amount of debt purchased			100,000,000		100,000,000
Maximum [Member] \| 5.500% Senior Notes, Due 2027 [Member]
Debt Instrument [Line Items]
Long-term debt, aggregate principal amount of debt purchased			325,000,000		325,000,000
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Credit facility amount			$ 1,350,000,000		$ 1,350,000,000
Revolving Credit Facility [Member] \| Operating Partnership Senior Credit Facility [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate			3.19%		3.19%
Revolving Credit Facility [Member] \| Operating Partnership Senior Credit Facility [Member] \| Term Loan B [Member]
Debt Instrument [Line Items]
Line of credit facility drawn			$ 1,350,000,000		$ 1,350,000,000
Unsecured Revolving Credit Facility [Member] \| MGM China Credit Facility [Member]
Debt Instrument [Line Items]
Line of credit facility			1,250,000,000		1,250,000,000
Term Loan [Member] \| MGM China Credit Facility [Member]
Debt Instrument [Line Items]
Line of credit facility drawn			$ 826,000,000		$ 826,000,000
Debt instrument, interest rate			3.88%		3.88%
Senior Credit Facility [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of credit facility			$ 1,500,000,000		$ 1,500,000,000
Line of credit facility drawn			$ 1,500,000,000		$ 1,500,000,000
Debt instrument, interest rate			2.93%		2.93%
Senior Credit Facility [Member] \| Revolving Credit Facility [Member] \| Maximum [Member] \| Subsequent Event [Member]
Debt Instrument [Line Items]
Liquidity level including unrestricted cash, cash equivalents								$ 600,000,000
Senior Credit Facility [Member] \| Revolving Credit Facility [Member] \| MGP BREIT Venture [Member]
Debt Instrument [Line Items]
Repayment and termination of existing revolving facility		$ 1,500,000,000
Loss on early retirement of debt		(4,000,000)
Senior Credit Facility [Member] \| Unsecured Revolving Credit Facility [Member] \| MGP BREIT Venture [Member]
Debt Instrument [Line Items]
Line of credit facility		$ 1,500,000,000
Credit facility, maturity date		2025-02