Condensed Consolidating Financial Information - Schedule of Condensed Consolidating Statement of Cash Flows Information (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Cash flows from operating activities
Net cash provided by (used in) operating activities	$ 1,810,401	$ 1,722,539	$ 2,206,411
Cash flows from investing activities
Capital expenditures, net of construction payable	(739,006)	(1,486,843)	(1,864,082)
Dispositions of property and equipment	2,578	25,612	718
Proceeds from Bellagio transaction	4,151,499	0	0
Proceeds from sale of Circus Circus Las Vegas and adjacent land	652,333	0	0
Proceeds from sale of business units and investment in unconsolidated affiliate	0	163,616	0
Investments in and advances to unconsolidated affiliates	(81,877)	(56,295)	(16,727)
Distributions from unconsolidated affiliates	100,700	322,631	301,211
Intercompany accounts	0	0	0
Northfield OpCo transaction	0
Other	(31,112)	(17,208)	(1,712)
Net cash provided by (used in) investing activities	3,519,434	(2,083,021)	(1,580,592)
Cash flows from financing activities
Net borrowings (repayments) under bank credit facilities – maturities of 90 days or less	(3,634,049)	1,242,259	15,001
Issuance of long-term debt	3,250,000	1,000,000	350,000
Retirement of senior notes and senior debentures	(3,764,167)	(2,265)	(502,669)
Debt issuance costs	(63,391)	(76,519)	(9,977)
Issuance of MGM Growth Properties Class A shares, net	1,250,006		387,548
Dividends paid to common shareholders	(271,288)	(260,592)	(252,014)
MGP dividends paid to consolidated subsidiaries	0	0	0
Distributions to noncontrolling interest owners	(223,303)	(184,932)	(170,402)
Purchases of common stock	(1,031,534)	(1,283,333)	(327,500)
Intercompany accounts	0	0	0
Other	(41,868)	(45,384)	(58,765)
Net cash provided by (used in) financing activities	(4,529,594)	389,234	(568,778)
Effect of exchange rate on cash	2,601	(1,985)	(3,627)
Cash flows from discontinued operations, net
Cash flows from operating activities	0	0
Cash flows used in investing activities	0	0
Cash flows used in financing activities	0	0
Net cash flows used in discontinued operations	0	0
Change in cash and cash equivalents classified as assets held for sale	0	0
Cash and cash equivalents
Net increase for the period	802,842	26,767	53,414
Balance, beginning of period	1,526,762	1,499,995	1,446,581
Balance, end of period	2,329,604	1,526,762	1,499,995
Reportable Legal Entities [Member] \| Parent [Member]
Cash flows from operating activities
Net cash provided by (used in) operating activities	(308,995)	(460,117)	(584,252)
Cash flows from investing activities
Capital expenditures, net of construction payable	0	0	0
Dispositions of property and equipment	0	0	0
Proceeds from Bellagio transaction	0
Proceeds from sale of Circus Circus Las Vegas and adjacent land	0
Proceeds from sale of business units and investment in unconsolidated affiliate		0
Investments in and advances to unconsolidated affiliates	0	0	0
Distributions from unconsolidated affiliates	0	0	0
Intercompany accounts	0	0	462,500
Northfield OpCo transaction	0
Other	0	0	0
Net cash provided by (used in) investing activities	0	0	462,500
Cash flows from financing activities
Net borrowings (repayments) under bank credit facilities – maturities of 90 days or less	(752,220)	377,500	122,500
Issuance of long-term debt	1,000,000	1,000,000	0
Retirement of senior notes and senior debentures	(3,764,167)	0	(502,669)
Debt issuance costs	(14,080)	(26,125)	0
Issuance of MGM Growth Properties Class A shares, net	0		0
Dividends paid to common shareholders	(271,288)	(260,592)	(252,014)
MGP dividends paid to consolidated subsidiaries	0	0	0
Distributions to noncontrolling interest owners	0	0	0
Purchases of common stock	(1,031,534)	(1,283,333)	(327,500)
Intercompany accounts	5,987,076	917,760	1,042,111
Other	(27,217)	(32,225)	(33,801)
Net cash provided by (used in) financing activities	1,126,570	692,985	48,627
Effect of exchange rate on cash	0	0	0
Cash flows from discontinued operations, net
Cash flows from operating activities	0	0
Cash flows used in investing activities	0	0
Cash flows used in financing activities	0	0
Net cash flows used in discontinued operations	0	0
Change in cash and cash equivalents classified as assets held for sale	0	0
Cash and cash equivalents
Net increase for the period	817,575	232,868	(73,125)
Balance, beginning of period	259,738	26,870	99,995
Balance, end of period	1,077,313	259,738	26,870
Reportable Legal Entities [Member] \| Guarantor Subsidiaries [Member]
Cash flows from operating activities
Net cash provided by (used in) operating activities	1,404,869	1,294,989	1,152,083
Cash flows from investing activities
Capital expenditures, net of construction payable	(504,105)	(697,462)	(482,024)
Dispositions of property and equipment	2,425	25,507	502
Proceeds from Bellagio transaction	4,151,499
Proceeds from sale of Circus Circus Las Vegas and adjacent land	652,333
Proceeds from sale of business units and investment in unconsolidated affiliate		163,616
Investments in and advances to unconsolidated affiliates	(81,877)	(56,295)	(16,727)
Distributions from unconsolidated affiliates	100,700	322,631	301,211
Intercompany accounts	(5,859,196)	(1,136,764)	(1,186,942)
Northfield OpCo transaction	(3,779)
Other	(4,500)	(13,416)	(1,754)
Net cash provided by (used in) investing activities	(2,082,181)	(1,358,381)	(1,385,734)
Cash flows from financing activities
Net borrowings (repayments) under bank credit facilities – maturities of 90 days or less	245,950	0	0
Issuance of long-term debt	0	0	0
Retirement of senior notes and senior debentures	0	(2,265)	0
Debt issuance costs	0	0	0
Issuance of MGM Growth Properties Class A shares, net	0		0
Dividends paid to common shareholders	0	0	0
MGP dividends paid to consolidated subsidiaries	0	0	0
Distributions to noncontrolling interest owners	(4,907)	0	0
Purchases of common stock	0	0	0
Intercompany accounts	456,571	207,015	248,626
Other	(47,686)	(6,979)	(11,644)
Net cash provided by (used in) financing activities	649,928	197,771	236,982
Effect of exchange rate on cash	0	0	0
Cash flows from discontinued operations, net
Cash flows from operating activities	0	0
Cash flows used in investing activities	0	0
Cash flows used in financing activities	0	0
Net cash flows used in discontinued operations	0	0
Change in cash and cash equivalents classified as assets held for sale	0	0
Cash and cash equivalents
Net increase for the period	(27,384)	134,379	3,331
Balance, beginning of period	445,423	311,044	307,713
Balance, end of period	418,039	445,423	311,044
Reportable Legal Entities [Member] \| Non-Guarantor MGP Subsidiaries [Member]
Cash flows from operating activities
Net cash provided by (used in) operating activities	100,706	556,801	482,578
Cash flows from investing activities
Capital expenditures, net of construction payable	0	(192)	(488)
Dispositions of property and equipment	0	0	0
Proceeds from Bellagio transaction	0
Proceeds from sale of Circus Circus Las Vegas and adjacent land	0
Proceeds from sale of business units and investment in unconsolidated affiliate		0
Investments in and advances to unconsolidated affiliates	0	0	0
Distributions from unconsolidated affiliates	0	0	0
Intercompany accounts	0	0	0
Northfield OpCo transaction	3,779
Other	0	0	0
Net cash provided by (used in) investing activities	3,779	(1,068,528)	(462,988)
Cash flows from financing activities
Net borrowings (repayments) under bank credit facilities – maturities of 90 days or less	(1,361,325)	727,750	(466,875)
Issuance of long-term debt	750,000	0	350,000
Retirement of senior notes and senior debentures	0	0	0
Debt issuance costs	(9,983)	(17,490)	(5,598)
Issuance of MGM Growth Properties Class A shares, net	1,250,006		387,548
Dividends paid to common shareholders	0	0	0
MGP dividends paid to consolidated subsidiaries	(371,759)	(333,192)	(290,091)
Distributions to noncontrolling interest owners	(161,976)	(121,068)	(95,344)
Purchases of common stock	0	0	0
Intercompany accounts	0	0	0
Other	(1,342)	0	0
Net cash provided by (used in) financing activities	93,621	256,000	(120,360)
Effect of exchange rate on cash	0	0	0
Cash flows from discontinued operations, net
Cash flows from operating activities	15,591	23,406
Cash flows used in investing activities	(12)	32,416
Cash flows used in financing activities	(37,900)	0
Net cash flows used in discontinued operations	(22,321)	55,822
Change in cash and cash equivalents classified as assets held for sale	(22,321)	55,822
Cash and cash equivalents
Net increase for the period	198,106	(255,727)	(100,770)
Balance, beginning of period	3,995	259,722	360,492
Balance, end of period	202,101	3,995	259,722
Reportable Legal Entities [Member] \| Non-Guarantor Other Subsidiaries [Member]
Cash flows from operating activities
Net cash provided by (used in) operating activities	629,412	330,866	1,156,002
Cash flows from investing activities
Capital expenditures, net of construction payable	(234,913)	(789,189)	(1,381,570)
Dispositions of property and equipment	153	105	216
Proceeds from Bellagio transaction	0
Proceeds from sale of Circus Circus Las Vegas and adjacent land	0
Proceeds from sale of business units and investment in unconsolidated affiliate		0
Investments in and advances to unconsolidated affiliates	0	0	0
Distributions from unconsolidated affiliates	0	0	0
Intercompany accounts	0	0	0
Northfield OpCo transaction	0
Other	(26,612)	(3,792)	42
Net cash provided by (used in) investing activities	(261,372)	(792,876)	(1,381,312)
Cash flows from financing activities
Net borrowings (repayments) under bank credit facilities – maturities of 90 days or less	(1,766,454)	137,009	359,376
Issuance of long-term debt	1,500,000	0	0
Retirement of senior notes and senior debentures	0	0	0
Debt issuance costs	(39,328)	(32,904)	(4,379)
Issuance of MGM Growth Properties Class A shares, net	0		0
Dividends paid to common shareholders	0	0	0
MGP dividends paid to consolidated subsidiaries	0	0	0
Distributions to noncontrolling interest owners	(56,420)	(63,864)	(75,058)
Purchases of common stock	0	0	0
Intercompany accounts	(212,692)	345,181	186,296
Other	(3,523)	(6,180)	(13,320)
Net cash provided by (used in) financing activities	(578,417)	379,242	452,915
Effect of exchange rate on cash	2,601	(1,985)	(3,627)
Cash flows from discontinued operations, net
Cash flows from operating activities	0	0
Cash flows used in investing activities	0	0
Cash flows used in financing activities	0	0
Net cash flows used in discontinued operations	0	0
Change in cash and cash equivalents classified as assets held for sale	0	0
Cash and cash equivalents
Net increase for the period	(207,776)	(84,753)	223,978
Balance, beginning of period	817,606	902,359	678,381
Balance, end of period	609,830	817,606	902,359
Elimination [Member]
Cash flows from operating activities
Net cash provided by (used in) operating activities	(15,591)	0	0
Cash flows from investing activities
Capital expenditures, net of construction payable	12	0	0
Dispositions of property and equipment	0	0	0
Proceeds from Bellagio transaction	0
Proceeds from sale of Circus Circus Las Vegas and adjacent land	0
Proceeds from sale of business units and investment in unconsolidated affiliate		0
Investments in and advances to unconsolidated affiliates	0	0	0
Distributions from unconsolidated affiliates	0	0	0
Intercompany accounts	5,859,196	1,136,764	724,442
Northfield OpCo transaction	0
Other	0	0	0
Net cash provided by (used in) investing activities	5,859,208	1,136,764	1,186,942
Cash flows from financing activities
Net borrowings (repayments) under bank credit facilities – maturities of 90 days or less	0	0	0
Issuance of long-term debt	0	0	0
Retirement of senior notes and senior debentures	0	0	0
Debt issuance costs	0	0	0
Issuance of MGM Growth Properties Class A shares, net	0		0
Dividends paid to common shareholders	0	0	0
MGP dividends paid to consolidated subsidiaries	371,759	333,192	290,091
Distributions to noncontrolling interest owners	0	0	0
Purchases of common stock	0	0	0
Intercompany accounts	(6,230,955)	(1,469,956)	(1,477,033)
Other	37,900	0	0
Net cash provided by (used in) financing activities	(5,821,296)	(1,136,764)	(1,186,942)
Effect of exchange rate on cash	0	0	0
Cash flows from discontinued operations, net
Cash flows from operating activities	(15,591)	(23,406)
Cash flows used in investing activities	12	(32,416)
Cash flows used in financing activities	37,900	0
Net cash flows used in discontinued operations	22,321	(55,822)
Change in cash and cash equivalents classified as assets held for sale	22,321	(55,822)
Cash and cash equivalents
Net increase for the period	22,321	0	0
Balance, beginning of period	0	0	0
Balance, end of period	22,321	0	0
Empire City [Member]
Cash flows from investing activities
Acquisition, net of cash acquired	(535,681)	0	0
Empire City [Member] \| Reportable Legal Entities [Member] \| Parent [Member]
Cash flows from investing activities
Acquisition, net of cash acquired	0
Empire City [Member] \| Reportable Legal Entities [Member] \| Guarantor Subsidiaries [Member]
Cash flows from investing activities
Acquisition, net of cash acquired	(535,681)
Empire City [Member] \| Reportable Legal Entities [Member] \| Non-Guarantor MGP Subsidiaries [Member]
Cash flows from investing activities
Acquisition, net of cash acquired	0
Empire City [Member] \| Reportable Legal Entities [Member] \| Non-Guarantor Other Subsidiaries [Member]
Cash flows from investing activities
Acquisition, net of cash acquired	0
Empire City [Member] \| Elimination [Member]
Cash flows from investing activities
Acquisition, net of cash acquired	$ 0
Northfield [Member]
Cash flows from investing activities
Acquisition, net of cash acquired		(1,034,534)
Northfield [Member] \| Reportable Legal Entities [Member] \| Parent [Member]
Cash flows from investing activities
Acquisition, net of cash acquired		0
Northfield [Member] \| Reportable Legal Entities [Member] \| Guarantor Subsidiaries [Member]
Cash flows from investing activities
Acquisition, net of cash acquired		33,802
Northfield [Member] \| Reportable Legal Entities [Member] \| Non-Guarantor MGP Subsidiaries [Member]
Cash flows from investing activities
Acquisition, net of cash acquired		(1,068,336)
Northfield [Member] \| Reportable Legal Entities [Member] \| Non-Guarantor Other Subsidiaries [Member]
Cash flows from investing activities
Acquisition, net of cash acquired		0
Northfield [Member] \| Elimination [Member]
Cash flows from investing activities
Acquisition, net of cash acquired		$ 0
National Harbor
Cash flows from investing activities
Acquisition, net of cash acquired			0
National Harbor \| Reportable Legal Entities [Member] \| Parent [Member]
Cash flows from investing activities
Acquisition, net of cash acquired			0
National Harbor \| Reportable Legal Entities [Member] \| Guarantor Subsidiaries [Member]
Cash flows from investing activities
Acquisition, net of cash acquired			0
National Harbor \| Reportable Legal Entities [Member] \| Non-Guarantor MGP Subsidiaries [Member]
Cash flows from investing activities
Acquisition, net of cash acquired			(462,500)
National Harbor \| Reportable Legal Entities [Member] \| Non-Guarantor Other Subsidiaries [Member]
Cash flows from investing activities
Acquisition, net of cash acquired			0
National Harbor \| Elimination [Member]
Cash flows from investing activities
Acquisition, net of cash acquired			$ 462,500

The net cash inflow (outflow) from intercompany advances from financing activities.

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Proceeds from (payments for) transactions between entities under operating partnership.

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Amount of cash inflow (outflow) of financing activities of discontinued operations. Financing activity cash flows include obtaining resources from owners and providing them with a return on, and a return of, their investment; borrowing money and repaying amounts borrowed, or settling the obligation; and obtaining and paying for other resources obtained from creditors on long-term credit.

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Amount of increase (decrease) from effect of exchange rate changes on cash and cash equivalents, and cash and cash equivalents restricted to withdrawal or usage; held in foreign currencies; attributable to disposal group, including, but not limited to, discontinued operations. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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