Condensed Consolidating Financial Information - Schedule of Condensed Consolidating Statement of Cash Flows Information (Detail) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018
Cash flows from operating activities
Net cash provided by (used in) operating activities	$ 967,833	$ 1,093,151
Cash flows from investing activities
Capital expenditures, net of construction payable	(321,618)	(861,761)
Dispositions of property and equipment	573	440
Investments in unconsolidated affiliates	(80,669)	(2,503)
Distributions from unconsolidated affiliates	90,000	200,000
Intercompany accounts	0	0
Northfield OpCo transaction	0
Other	(30,170)	(15,609)
Net cash used in investing activities	(877,565)	(679,433)
Cash flows from financing activities
Net borrowings (repayments) under bank credit facilities – maturities of 90 days or less	(1,979,956)	(360,874)
Issuance of long-term debt	3,250,000	1,000,000
Retirement of senior notes and senior debentures	(1,759,926)	(2,265)
Debt issuance costs	(45,546)	(64,777)
Issuance of MGM Growth Properties Class A shares, net	613,299
Dividends paid to common shareholders	(138,215)	(133,334)
MGP dividends paid to consolidated subsidiaries	0	0
Distributions to noncontrolling interest owners	(102,418)	(101,407)
Purchases of common stock	(281,833)	(957,264)
Intercompany accounts	0	0
Other	(13,184)	(18,230)
Net cash used in financing activities	(457,779)	(638,151)
Effect of exchange rate on cash	1,340	(2,690)
Cash flows from (used in) discontinued operations
Cash flows from operating activities	0
Cash flows used in investing activities	0
Cash flows used in financing activities	0
Net cash flows used in discontinued operations	0
Change in cash and cash equivalents classified as assets held for sale	0
Cash and cash equivalents
Net decrease for the period	(366,171)	(227,123)
Balance, beginning of period	1,526,762	1,499,995
Balance, end of period	1,160,591	1,272,872
Empire City [Member]
Cash flows from investing activities
Acquisition, net of cash acquired	(535,681)	0
Reportable Legal Entities [Member] \| Parent [Member]
Cash flows from operating activities
Net cash provided by (used in) operating activities	(284,892)	(224,359)
Cash flows from investing activities
Capital expenditures, net of construction payable	0	0
Dispositions of property and equipment	0	0
Investments in unconsolidated affiliates	0	0
Distributions from unconsolidated affiliates	0	0
Intercompany accounts	0	0
Northfield OpCo transaction	0
Other	0	0
Net cash used in investing activities	0	0
Cash flows from financing activities
Net borrowings (repayments) under bank credit facilities – maturities of 90 days or less	310,000	(141,250)
Issuance of long-term debt	1,000,000	1,000,000
Retirement of senior notes and senior debentures	(1,721,698)	0
Debt issuance costs	(14,080)	(14,414)
Issuance of MGM Growth Properties Class A shares, net	0
Dividends paid to common shareholders	(138,215)	(133,334)
MGP dividends paid to consolidated subsidiaries	0	0
Distributions to noncontrolling interest owners	0	0
Purchases of common stock	(281,833)	(957,264)
Intercompany accounts	913,889	505,289
Other	(6,808)	(9,393)
Net cash used in financing activities	61,255	249,634
Effect of exchange rate on cash	0	0
Cash flows from (used in) discontinued operations
Cash flows from operating activities	0
Cash flows used in investing activities	0
Cash flows used in financing activities	0
Net cash flows used in discontinued operations	0
Change in cash and cash equivalents classified as assets held for sale	0
Cash and cash equivalents
Net decrease for the period	(223,637)	25,275
Balance, beginning of period	259,738	26,870
Balance, end of period	36,101	52,145
Reportable Legal Entities [Member] \| Guarantor Subsidiaries [Member]
Cash flows from operating activities
Net cash provided by (used in) operating activities	1,142,767	624,484
Cash flows from investing activities
Capital expenditures, net of construction payable	(212,513)	(367,713)
Dispositions of property and equipment	505	435
Investments in unconsolidated affiliates	(80,669)	(2,503)
Distributions from unconsolidated affiliates	90,000	200,000
Intercompany accounts	(1,018,976)	(515,927)
Northfield OpCo transaction	(3,779)
Other	(3,500)	(9,916)
Net cash used in investing activities	(1,764,613)	(695,624)
Cash flows from financing activities
Net borrowings (repayments) under bank credit facilities – maturities of 90 days or less	245,950	0
Issuance of long-term debt	0	0
Retirement of senior notes and senior debentures	(38,228)	(2,265)
Debt issuance costs	0	0
Issuance of MGM Growth Properties Class A shares, net	0
Dividends paid to common shareholders	0	0
MGP dividends paid to consolidated subsidiaries	0	0
Distributions to noncontrolling interest owners	0	0
Purchases of common stock	0	0
Intercompany accounts	414,567	48,052
Other	(43,411)	(4,200)
Net cash used in financing activities	578,878	41,587
Effect of exchange rate on cash	0	0
Cash flows from (used in) discontinued operations
Cash flows from operating activities	0
Cash flows used in investing activities	0
Cash flows used in financing activities	0
Net cash flows used in discontinued operations	0
Change in cash and cash equivalents classified as assets held for sale	0
Cash and cash equivalents
Net decrease for the period	(42,968)	(29,553)
Balance, beginning of period	445,423	311,043
Balance, end of period	402,455	281,490
Reportable Legal Entities [Member] \| Non-Guarantor MGP Subsidiaries [Member]
Cash flows from operating activities
Net cash provided by (used in) operating activities	(243,990)	284,333
Cash flows from investing activities
Capital expenditures, net of construction payable	0	(190)
Dispositions of property and equipment	0	0
Investments in unconsolidated affiliates	0	0
Distributions from unconsolidated affiliates	0	0
Intercompany accounts	0	0
Northfield OpCo transaction	3,779
Other	0	0
Net cash used in investing activities	3,779	(190)
Cash flows from financing activities
Net borrowings (repayments) under bank credit facilities – maturities of 90 days or less	(805,200)	(13,000)
Issuance of long-term debt	750,000	0
Retirement of senior notes and senior debentures	0	0
Debt issuance costs	(9,983)	(17,490)
Issuance of MGM Growth Properties Class A shares, net	613,299
Dividends paid to common shareholders	0	0
MGP dividends paid to consolidated subsidiaries	(184,537)	(163,913)
Distributions to noncontrolling interest owners	(73,797)	(59,553)
Purchases of common stock	0	0
Intercompany accounts	0	0
Other	0	0
Net cash used in financing activities	289,782	(253,956)
Effect of exchange rate on cash	0	0
Cash flows from (used in) discontinued operations
Cash flows from operating activities	15,591
Cash flows used in investing activities	(12)
Cash flows used in financing activities	(37,900)
Net cash flows used in discontinued operations	(22,321)
Change in cash and cash equivalents classified as assets held for sale	(22,321)
Cash and cash equivalents
Net decrease for the period	49,571	30,187
Balance, beginning of period	3,995	259,722
Balance, end of period	53,566	289,909
Reportable Legal Entities [Member] \| Non-Guarantor Other Subsidiaries [Member]
Cash flows from operating activities
Net cash provided by (used in) operating activities	369,539	408,693
Cash flows from investing activities
Capital expenditures, net of construction payable	(109,117)	(493,858)
Dispositions of property and equipment	68	5
Investments in unconsolidated affiliates	0	0
Distributions from unconsolidated affiliates	0	0
Intercompany accounts	0	0
Northfield OpCo transaction	0
Other	(26,670)	(5,693)
Net cash used in investing activities	(135,719)	(499,546)
Cash flows from financing activities
Net borrowings (repayments) under bank credit facilities – maturities of 90 days or less	(1,730,706)	(206,624)
Issuance of long-term debt	1,500,000	0
Retirement of senior notes and senior debentures	0	0
Debt issuance costs	(21,483)	(32,873)
Issuance of MGM Growth Properties Class A shares, net	0
Dividends paid to common shareholders	0	0
MGP dividends paid to consolidated subsidiaries	0	0
Distributions to noncontrolling interest owners	(28,621)	(41,854)
Purchases of common stock	0	0
Intercompany accounts	(124,943)	126,499
Other	(865)	(4,637)
Net cash used in financing activities	(406,618)	(159,489)
Effect of exchange rate on cash	1,340	(2,690)
Cash flows from (used in) discontinued operations
Cash flows from operating activities	0
Cash flows used in investing activities	0
Cash flows used in financing activities	0
Net cash flows used in discontinued operations	0
Change in cash and cash equivalents classified as assets held for sale	0
Cash and cash equivalents
Net decrease for the period	(171,458)	(253,032)
Balance, beginning of period	817,606	902,360
Balance, end of period	646,148	649,328
Reportable Legal Entities [Member] \| Empire City [Member] \| Parent [Member]
Cash flows from investing activities
Acquisition, net of cash acquired	0
Reportable Legal Entities [Member] \| Empire City [Member] \| Guarantor Subsidiaries [Member]
Cash flows from investing activities
Acquisition, net of cash acquired	(535,681)
Reportable Legal Entities [Member] \| Empire City [Member] \| Non-Guarantor MGP Subsidiaries [Member]
Cash flows from investing activities
Acquisition, net of cash acquired	0
Reportable Legal Entities [Member] \| Empire City [Member] \| Non-Guarantor Other Subsidiaries [Member]
Cash flows from investing activities
Acquisition, net of cash acquired	0
Elimination [Member]
Cash flows from operating activities
Net cash provided by (used in) operating activities	(15,591)	0
Cash flows from investing activities
Capital expenditures, net of construction payable	12	0
Dispositions of property and equipment	0	0
Investments in unconsolidated affiliates	0	0
Distributions from unconsolidated affiliates	0	0
Intercompany accounts	1,018,976	515,927
Northfield OpCo transaction	0
Other	0	0
Net cash used in investing activities	1,018,988	515,927
Cash flows from financing activities
Net borrowings (repayments) under bank credit facilities – maturities of 90 days or less	0	0
Issuance of long-term debt	0	0
Retirement of senior notes and senior debentures	0	0
Debt issuance costs	0	0
Issuance of MGM Growth Properties Class A shares, net	0
Dividends paid to common shareholders	0	0
MGP dividends paid to consolidated subsidiaries	184,537	163,913
Distributions to noncontrolling interest owners	0	0
Purchases of common stock	0	0
Intercompany accounts	(1,203,513)	(679,840)
Other	37,900	0
Net cash used in financing activities	(981,076)	(515,927)
Effect of exchange rate on cash	0	0
Cash flows from (used in) discontinued operations
Cash flows from operating activities	(15,591)
Cash flows used in investing activities	12
Cash flows used in financing activities	37,900
Net cash flows used in discontinued operations	22,321
Change in cash and cash equivalents classified as assets held for sale	22,321
Cash and cash equivalents
Net decrease for the period	22,321	0
Balance, beginning of period	0	0
Balance, end of period	22,321	$ 0
Elimination [Member] \| Empire City [Member]
Cash flows from investing activities
Acquisition, net of cash acquired	$ 0

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

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The cash inflow from the additional capital contribution to the entity.

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The cash inflow from the sale of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale.

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