Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

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Debt instrument maturity year.

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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.

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

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

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

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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.

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

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

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The percentage points added to the reference rate to compute the variable rate on the interest rate derivative.

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No definition available.

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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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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.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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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.

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The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

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Long-Term Debt - Additional Information (Detail) - USD ($)	1 Months Ended				3 Months Ended	6 Months Ended	12 Months Ended
	May 31, 2019	Apr. 30, 2019	Feb. 28, 2019	Jan. 31, 2019	Jun. 30, 2019	Jun. 30, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Current portion of long-term debt, net of debt issuance costs					$ 0	$ 0	$ 43,411,000
Credit facility amount					14,799,591,000	14,799,591,000	15,253,239,000
Long-term debt, fair value					15,500,000,000	15,500,000,000	15,100,000,000
Interest Rate Swap [Member] \| Cash Flow Hedges [Member]
Debt Instrument [Line Items]
Notional amount					$ 900,000,000	$ 900,000,000	$ 400,000,000
Weighted Average fixed interest rate					1.801%	1.801%	2.735%
LIBOR [Member] \| Minimum [Member] \| Interest Rate Swap [Member] \| Cash Flow Hedges [Member]
Debt Instrument [Line Items]
Derivative basis spread on variable rate					0.00%	0.00%	0.00%
Term Loan A [Member] \| Operating Partnership Senior Credit Facility [Member]
Debt Instrument [Line Items]
Credit facility amount					$ 470,000,000	$ 470,000,000
Debt instrument, interest rate					4.15%	4.15%
Term Loan B [Member] \| Operating Partnership Senior Credit Facility [Member]
Debt Instrument [Line Items]
Credit facility amount					$ 1,790,000,000	$ 1,790,000,000
Debt instrument, interest rate					4.40%	4.40%
Term Loan B [Member] \| Interest Rate Swap [Member] \| Cash Flow Hedges [Member]
Debt Instrument [Line Items]
Notional amount					$ 1,200,000,000	$ 1,200,000,000
Weighted Average fixed interest rate					1.844%	1.844%
Term Loan B [Member] \| LIBOR [Member] \| Minimum [Member] \| Interest Rate Swap [Member] \| Cash Flow Hedges [Member]
Debt Instrument [Line Items]
Derivative basis spread on variable rate					0.00%	0.00%
5.75% Operating Partnership senior notes, due 2027 [Member]
Debt Instrument [Line Items]
Long-term debt, principal amount				$ 750,000,000	$ 750,000,000	$ 750,000,000
Long-term debt, interest rate (as a percent)				5.75%	5.75%	5.75%
Long-term debt, maturity year				2027		2027
5.75% Operating Partnership senior notes, due 2027 [Member] \| Bridge Facility [Member] \| Empire City [Member]
Debt Instrument [Line Items]
Long-term debt, principal amount					$ 246,000,000	$ 246,000,000
Long-term debt, interest rate (as a percent)					5.75%	5.75%
Long-term debt, maturity year						2027
Senior Notes 5.50%, Due in 2027 [Member]
Debt Instrument [Line Items]
Long-term debt, principal amount		$ 1,000,000,000.0
Long-term debt, interest rate (as a percent)		5.50%
Long-term debt, maturity year		2027
6.75% senior notes, due 2020 [Member]
Debt Instrument [Line Items]
Long-term debt, principal amount					$ 1,000,000,000	$ 1,000,000,000	$ 1,000,000,000
Long-term debt, interest rate (as a percent)		6.75%			6.75%	6.75%	6.75%
Long-term debt, maturity year		2020				2020	2020
Long-term debt, aggregate principal amount of debt purchased		$ 639,000,000
5.25% senior notes, due 2020 [Member]
Debt Instrument [Line Items]
Long-term debt, principal amount					$ 500,000,000	$ 500,000,000	$ 500,000,000
Long-term debt, interest rate (as a percent)		5.25%			5.25%	5.25%	5.25%
Long-term debt, maturity year		2020				2020	2020
Long-term debt, aggregate principal amount of debt purchased		$ 233,000,000
8.625% senior notes, due 2019 [Member]
Debt Instrument [Line Items]
Repayments of term loan			$ 850,000,000
Long-term debt, principal amount							$ 850,000,000
Long-term debt, interest rate (as a percent)			8.625%				8.625%
Long-term debt, maturity year							2019
5.375% MGM China senior notes, due 2024 [Member]
Debt Instrument [Line Items]
Long-term debt, principal amount	$ 750,000,000				$ 750,000,000	$ 750,000,000
Long-term debt, interest rate (as a percent)	5.375%				5.375%	5.375%
Long-term debt, maturity year	2024					2024
5.875% MGM China senior notes, due 2026 [Member]
Debt Instrument [Line Items]
Long-term debt, principal amount	$ 750,000,000				$ 750,000,000	$ 750,000,000
Long-term debt, interest rate (as a percent)	5.875%				5.875%	5.875%
Long-term debt, maturity year	2026					2026
Senior Credit Facility [Member] \| Term Loan A [Member]
Debt Instrument [Line Items]
Credit facility amount					$ 750,000,000	$ 750,000,000
Debt instrument, interest rate					4.40%	4.40%
MGM China Credit Facility [Member]
Debt Instrument [Line Items]
Current portion of long-term debt, net of debt issuance costs							$ 43,000,000
Credit facility amount					$ 700,862,000	$ 700,862,000	$ 2,433,562,000
Revolving Credit Facility [Member] \| Operating Partnership Senior Credit Facility [Member]
Debt Instrument [Line Items]
Line of credit facility					1,350,000,000	1,350,000,000
Line of credit facility drawn					0	0
Revolving Credit Facility [Member] \| MGM China Credit Facility [Member]
Debt Instrument [Line Items]
Line of credit facility					1,000,000,000.0	1,000,000,000.0
Line of credit facility drawn					$ 102,000,000	$ 102,000,000
Debt instrument, interest rate					4.77%	4.77%
Revolving Credit Facility [Member] \| Senior Credit Facility [Member]
Debt Instrument [Line Items]
Line of credit facility					$ 1,500,000,000	$ 1,500,000,000
Line of credit facility drawn					$ 310,000,000	$ 310,000,000
Debt instrument, interest rate					4.39%	4.39%
Term loans [Member] \| MGM China Credit Facility [Member]
Debt Instrument [Line Items]
Line of credit facility					$ 599,000,000	$ 599,000,000
Repayments of term loan					$ 100,000,000	$ 199,000,000
Debt instrument, interest rate					4.77%	4.77%