LONG-TERM DEBT - Additional Information (Details) - USD ($)			1 Months Ended				3 Months Ended				12 Months Ended
	Jan. 17, 2019	Feb. 10, 2014	Dec. 19, 2018	Apr. 18, 2017	Apr. 21, 2016	Apr. 17, 2015	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Nov. 13, 2019	Apr. 17, 2019	Dec. 20, 2018	Dec. 04, 2018
Debt Instrument [Line Items]
Long-term Debt, Gross							$ 2,000,000				$ 0	$ 2,000,000
Debt Instrument, Interest Rate, Stated Percentage							9.25%					9.25%
Gain Losses on Extinguishment of Debt											$ 0	$ (1,809,000)
Debt Instrument, Interest Rate Terms											The 2018 Credit Facility contains customary representations and warranties and events of default, affirmative and negative covenants (in each case, subject to materiality exceptions and qualifications). The 2018 Credit Facility also contains certain financial covenants, including a maintenance covenant requiring the Company's total gross leverage ratio to be not greater than 8.0 to 1.00 in 2019, 7.5 to 1.00 in 2020, 7.25 to 1.00 in 2021 and 6.75 to 1.00 in 2022. As of December 31, 2019, the Company was in compliance with all of its financial covenants under the 2018 Credit Facility.
Interest Expense, Total											$ 81,400,000	$ 76,667,000
Debt Instrument Additional Interest Payment Term On Prepayment				Beginning with the interest payment date occurring in June 2017 and ending in March 2023, the Company will be required to repay principal, to the extent then outstanding, equal to 1∕4 of 1% of the aggregate initial principal amount of all term loans incurred on the effective date of the 2017 Credit Facility
Long-term Debt, Maturity Date							Dec. 31, 2022					Dec. 31, 2022
Comcast Note [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount							$ 11,900,000					$ 11,900,000		$ 11,900,000
Long-term Debt, Gross							11,900,000					11,900,000
Debt Instrument, Interest Rate, Stated Percentage											10.47%
Senior Secured Notes Due 2022 [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross						$ 350,000,000
Debt Instrument, Description						an original issue price of 100.0% plus accrued interest
9.25% Senior Subordinated Notes due February 2020 [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross							2,000,000					2,000,000
Debt Instrument, Interest Rate, Stated Percentage											9.25%
Gain Losses on Extinguishment of Debt							2,800,000
Debt Instrument, Repurchase Amount							$ 243,000,000					243,000,000
Debt Instrument, Redemption Price, Percentage							100.88%
Write off of Deferred Debt Issuance Cost							$ 649,000
Premium Paid to the Bondholders							2,100,000
Debt Instrument, Redemption Period, Start Date											Feb. 15, 2019
9.25% Senior Subordinated Notes due February 2020 [Member] | Private Offering [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross		$ 335,000,000
Debt Instrument, Periodic Payment		$ 15,500,000
Senior Subordinated Notes due April 2022 [Member]
Debt Instrument [Line Items]
Debt Instrument, Description						The 2022 Notes were offered at an original issue price of 100.0% plus accrued interest from April 17, 2015, and will mature on April 15, 2022.
MGM National Harbor Loan [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount															$ 50,000,000
Long-term Debt, Gross							50,100,000				$ 52,100,000	$ 50,100,000
Debt Instrument, Interest Rate, Stated Percentage											7.00%
Debt Instrument, Unamortized Discount (Premium), Net											$ 1,000,000
Long Term Debt Percentage Paid In Kind											4.00%
Debt Issuance Costs, Net											$ 1,700,000
Asset Backed Credit Facility [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount													$ 37,500,000
Letters of Credit											848,000		7,500,000
Line of Credit Facility, Maximum Borrowing Capacity					$ 25,000,000								$ 25,000,000
Percentage Borrowing Of Eligible Accounts					(85.00%)
2017 Credit Facility [Member]
Debt Instrument [Line Items]
Covenant Compliance Description For Maintaining Interest Coverage Ratio												maintaining an interest coverage ratio of no less than:1.25 to 1.00 on June 30, 2017 and the last day of each fiscal quarter thereafter.
Covenant Compliance Description For Maintaining Total Leverage Ratio												)  maintaining a senior leverage ratio of no greater than:5.85 to 1.00 on June 30, 2017 and the last day of each fiscal quarter thereafter.
Repayments of Long-term Debt, Total			$ 20,000,000								3,300,000	$ 23,400,000
Long-term Debt, Gross				$ 350,000,000							320,600,000
Debt Instrument, Description				The 2017 Credit Facility matures on the earlier of (i) April 18, 2023, or (ii) in the event such debt is not repaid or refinanced, 91 days prior to the maturity of the Company's 2022 Notes (as defined below). At the Company's election, the interest rate on borrowings under the 2017 Credit Facility are based on either (i) the then applicable base rate (as defined in the 2017 Credit Facility) as, for any day, a rate per annum (rounded upward, if necessary, to the next 1/100th of 1%) equal to the greater of (a) the prime rate published in the Wall Street Journal, (b) 1/2 of 1% in excess rate of the overnight Federal Funds Rate at any given time, (c) the one-month LIBOR rate commencing on such day plus 1.00%) and (d) 2%, or (ii) the then applicable LIBOR rate (as defined in the 2017 Credit Facility). The average interest rate was approximately 6.27% for 2019 and was 6.07% for 2018.The 2017 Credit Facility is (i) guaranteed by each entity that guarantees the Company's 2022 Notes on a pari passu basis with the guarantees of the 2022 Notes and (ii) secured on a pari passu basis with the Company's 2022 Notes. The Company's obligations under the 2017 Credit Facility are secured, subject to permitted liens and except for certain excluded assets (i) on a first priority basis by certain notes priority collateral, and (ii) on a second priority basis by collateral for the Company's asset-backed line of credit.
Debt Instrument, Interest Rate Terms				The 2017 Credit Facility contains customary representations and warranties and events of default, affirmative and negative covenants (in each case, subject to materiality exceptions and qualifications) which may be more restrictive than those governing the 2022 Notes. The 2017 Credit Facility also contains certain financial covenants, including a maintenance covenant requiring the Company's interest expense coverage ratio (defined as the ratio of consolidated EBITDA to consolidated interest expense) to be greater than or equal to 1.25 to 1.00 and its total senior secured leverage ratio (defined as the ratio of consolidated net senior secured indebtedness to consolidated EBITDA) to be less than or equal to 5.85 to 1.00.
2018 Credit Facility [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount															$ 192,000,000
Long-term Debt, Gross							$ 192,000,000				$ 167,100,000	192,000,000				$ 192,000,000
Debt Instrument, Description											The 2018 Credit Facility matures on December 31, 2022 (the "Maturity Date"). Interest rates on borrowings under the 2018 Credit Facility will be either (i) from the Funding Date to the Maturity Date, 12.875% per annum, (ii) 11.875% per annum, once 50% of the term loan borrowings have been repaid or (iii) 10.875% per annum, once 75% of the term loan borrowings have been repaid. Interest payments begin on the last day of the 3-month period commencing on the Funding Date.
Debt Instrument, Interest Rate Terms											Borrowings under the 2018 Credit Facility are subject to customary conditions precedent, as well as a requirement under the 2018 Credit Facility that (i) the Company's total gross leverage ratio on a pro forma basis be not greater than 8:00 to 1:00 (this total gross leverage ratio test steps down as described below), (ii) neither of the administrative agents under the Company's existing credit facilities nor the trustee under the Company's existing senior secured notes due 2022 have objected to the terms of the new credit documents and (iii) certification by the Company that the terms and conditions of the 2018 Credit Facility satisfy the requirements of the definition of "Permitted Refinancing" (as defined in the agreements governing the Company's existing credit facilities) and neither of the administrative agents under the Company's existing credit facilities notifies the Company within five (5) business days prior to funding the borrowings under the 2018 Credit Facility that it disagrees with such determination (including a reasonable description of the basis upon which it disagrees).
Interest Expense, Total											$ 3,900,000	$ 2,900,000
Debt Instrument Additional Interest Payment Term On Prepayment											The term loans could have been voluntarily prepaid prior to February 15, 2020 subject to payment of a prepayment premium. The Company is required to repay principal to the extent then outstanding on each quarterly interest payment date, commencing on the last business day in March 2019, equal to one quarter of 7.5% of the aggregate initial principal amount of all term loans incurred on the Funding Date to December 2019, commencing on the last business day in March 2020, one quarter of 10.0% of the aggregate initial principal amount of all term loans incurred on the Funding Date to December 2021, and, commencing on the last business day in March 2021, one quarter of 12.5% of the aggregate initial principal amount of all term loans incurred on the Funding Date to December 2022. The Company is also required to use 75% of excess cash flow ("ECF payment") as defined in the 2018 Credit Facility, which exclude any distributions to the Company or its restricted subsidiaries in respect of its interests in the MGM National Harbor to repay outstanding term loans at par, paid semiannually and to use 100% of all distributions to the Company or its restricted subsidiaries received in respect of its interest in the MGM National Harbor to repay outstanding terms loans at par. During the year ended December 31, 2019, the Company repaid approximately $24.9 million, under the 2018 Credit Facility. Included in the repayments made during the year ended December 31, 2019 was approximately $3.5 million in ECF payments in accordance with the agreement.
Debt Instrument, Unamortized Discount (Premium), Net											$ 3,800,000
2018 Credit Facility [Member] | Debt Financing Cost [Member]
Debt Instrument [Line Items]
Debt Issuance Costs, Net											$ 875,000
Senior Subordinated Notes Due From 2020 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		100.00%				7.375%
Gain Losses on Extinguishment of Debt								$ 120,000	$ 626,000	$ 239,000
Debt Instrument, Repurchase Amount								$ 5,000,000	$ 14,000,000	$ 11,000,000
Debt Instrument, Redemption Price, Percentage	100.00%							97.25%	95.125%	97.375%