MGP Lessor S-4 23 Nov 19 Registration of securities issued in business combination transactions Financial data

Cover Page

Cover Page	9 Months Ended
	Sep. 30, 2019
Cover [Abstract]
Document Type	S-4
Amendment Flag	false
Document Period End Date	Sep. 30, 2019
Entity Registrant Name	MGM Growth Properties Operating Partnership LP
Entity Central Index Key	0001691299
Entity Filer Category	Non-accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018	Dec. 31, 2017
ASSETS
Real estate investments, net	$ 10,894,121	$ 10,506,129	$ 10,021,938
Lease incentive asset	532,186	0
Cash and cash equivalents	153,526	3,995	259,722
Tenant and other receivables, net	463	7,668	6,385
Prepaid expenses and other assets	27,413	34,813	18,487
Above market lease, asset	41,834	43,014	44,588
Operating lease right-of-use assets	280,020	0
Assets held for sale	0	355,688	0
Total assets	11,929,563	10,951,307	10,351,120
Liabilities
Debt, net	4,847,408	4,666,949	3,934,628
Due to MGM Resorts International and affiliates	298	227	962
Accounts payable, accrued expenses and other liabilities	59,937	20,796	10,240
Above market lease, liability	0	46,181	47,069
Accrued interest	37,407	26,096	22,565
Dividend and distribution payable	138,730	119,055	111,733
Deferred revenue	95,306	163,926	127,640
Deferred income taxes, net	29,721	33,634	28,544
Operating lease liabilities	336,452	0
Liabilities related to assets held for sale	0	28,937	0
Total liabilities	5,545,259	5,105,801	4,283,381
Commitments and contingencies
Shareholders' equity
Class A shares	0	0	0
Additional paid-in capital	2,307,463	1,712,671	1,716,490
Accumulated deficit	(216,824)	(150,908)	(94,948)
Accumulated other comprehensive income (loss)	(16,129)	4,208	3,108
Total Class A shareholders' equity	2,074,510	1,565,971	1,624,650
Noncontrolling interest	4,309,794	4,279,535	4,443,089
Total shareholders' equity	6,384,304	5,845,506	6,067,739
Partners' capital
Total liabilities and shareholders' equity	11,929,563	10,951,307	10,351,120
MGP Operating Partnership
ASSETS
Real estate investments, net	10,894,121	10,506,129	10,021,938
Lease incentive asset	532,186	0
Cash and cash equivalents	153,526	3,995	259,722
Tenant and other receivables, net	463	7,668	6,385
Prepaid expenses and other assets	27,413	34,813	18,487
Above market lease, asset	41,834	43,014	44,588
Operating lease right-of-use assets	280,020	0
Assets held for sale	0	355,688	0
Total assets	11,929,563	10,951,307	10,351,120
Liabilities
Debt, net	4,847,408	4,666,949	3,934,628
Due to MGM Resorts International and affiliates	298	227	962
Accounts payable, accrued expenses and other liabilities	59,937	20,796	10,240
Above market lease, liability	0	46,181	47,069
Accrued interest	37,407	26,096	22,565
Dividend and distribution payable	138,730	119,055	111,733
Deferred revenue	95,306	163,926	127,640
Deferred income taxes, net	29,721	33,634	28,544
Operating lease liabilities	336,452	0
Liabilities related to assets held for sale	0	28,937	0
Total liabilities	5,545,259	5,105,801	4,283,381
Commitments and contingencies
Partners' capital
General partner	0	0	0
Limited partners	6,384,304	5,845,506	6,067,739
Total partners' capital	6,384,304	5,845,506	6,067,739
Total liabilities and shareholders' equity	$ 11,929,563	$ 10,951,307	$ 10,351,120

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares	Sep. 30, 2019	Dec. 31, 2018	Dec. 31, 2017
Shareholders' equity
Common stock, par value (in dollars per share)	$ 0	$ 0	$ 0
Common stock, shares authorized (in shares)	1,000,000,000	1,000,000,000	1,000,000,000
Common stock, shares issued (in shares)	95,468,067	70,911,166	70,896,795
Common stock, shares outstanding (in shares)	95,468,067	70,911,166	70,896,795
MGP Operating Partnership
Partners' capital
Partners' capital, units issued (in shares)	295,170,610	266,045,289	266,030,918
Partners' capital, units outstanding (in shares)	295,170,610	266,045,289	266,030,918

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Revenues	$ 226,011	$ 216,659	$ 655,193	$ 652,888	$ 869,495	$ 765,695	$ 467,548
Expenses
Depreciation and amortization	71,957	63,468	223,062	199,933	266,622	260,455	220,667
Property transactions, net	9,921	339	11,344	18,851	20,319	34,022	4,684
Ground lease and other reimbursable expenses	5,920	29,168	17,760	90,435	119,531	88,254	68,063
Amortization of above market lease, net	0	171	0	514	686	686	286
Acquisition-related expenses	92	1,931	8,891	4,603	6,149	17,304	10,178
General and administrative	4,476	3,358	12,305	10,021	16,048	12,189	9,896
Expenses, net	92,366	98,435	273,362	324,357	429,355	412,910	313,774
Operating income					440,140	352,785	153,774
Other income (expense)
Interest income	241	163	2,189	2,473	2,501	3,907	774
Interest expense	(63,048)	(58,743)	(190,973)	(157,249)	(215,532)	(184,175)	(116,212)
Other	(306)	(1,020)	(806)	(6,409)	(7,191)	(1,621)	(726)
Non-operating income (expense)	(63,113)	(59,600)	(189,590)	(161,185)	(220,222)	(181,889)	(116,164)
Income from continuing operations before income taxes	70,532	58,624	192,241	167,346	219,918	170,896	37,610
Provision for income taxes	(1,979)	(2,650)	(5,771)	(5,144)	(5,779)	(4,906)	(2,264)
Income from continuing operations	68,553	55,974	186,470	162,202	214,139	165,990	35,346
Income from discontinued operations	0	13,949	16,216	13,949	30,563	0	0
Net income	68,553	69,923	202,686	176,151	244,702	165,990	35,346
Less: Net income attributable to noncontrolling interest	(46,038)	(50,439)	(138,358)	(127,691)	(177,637)	(124,215)	(5,408)
Net income attributable to Class A shareholders	$ 22,515	$ 19,484	$ 64,328	$ 48,460	$ 67,065	$ 41,775	$ 29,938
Weighted average Class A shares outstanding:
Basic (in shares)	93,165,443	71,005,052	89,440,552	70,991,129	70,997,589	61,733,136	57,502,158
Diluted (in shares)	93,322,940	71,201,791	89,645,109	71,174,270	71,185,674	61,916,546	57,751,489
Class A Shares
Weighted average Class A shares outstanding:
Income from continuing operations per Class A share (basic) (in usd per share)	$ 0.24	$ 0.22	$ 0.67	$ 0.63	$ 0.83	$ 0.68	$ 0.52
Income from discontinued operations per Class A share (basic) (in usd per share)	0	0.05	0.05	0.05	0.11	0	0
Net income per Class A share (basic) (in usd per share)	0.24	0.27	0.72	0.68	0.94	0.68	0.52
Income from continuing operations per Class A share (diluted) (in usd per share)	0.24	0.22	0.67	0.63	0.83	0.67	0.52
Income from discontinued operations per Class A share (diluted) (in usd per share)	0	0.05	0.05	0.05	0.11	0	0
Net income per Class A share (diluted) (in usd per share)	$ 0.24	$ 0.27	$ 0.72	$ 0.68	$ 0.94	$ 0.67	$ 0.52
MGP Operating Partnership
Revenues	$ 226,011	$ 216,659	$ 655,193	$ 652,888	$ 869,495	$ 765,695	$ 467,548
Expenses
Depreciation and amortization	71,957	63,468	223,062	199,933	266,622	260,455	220,667
Property transactions, net	9,921	339	11,344	18,851	20,319	34,022	4,684
Ground lease and other reimbursable expenses	5,920	29,168	17,760	90,435	119,531	88,254	68,063
Amortization of above market lease, net	0	171	0	514	686	686	286
Acquisition-related expenses	92	1,931	8,891	4,603	6,149	17,304	10,178
General and administrative	4,476	3,358	12,305	10,021	16,048	12,189	9,896
Expenses, net	92,366	98,435	273,362	324,357	429,355	412,910	313,774
Operating income					440,140	352,785	153,774
Other income (expense)
Interest income	241	163	2,189	2,473	2,501	3,907	774
Interest expense	(63,048)	(58,743)	(190,973)	(157,249)	(215,532)	(184,175)	(116,212)
Other	(306)	(1,020)	(806)	(6,409)	(7,191)	(1,621)	(726)
Non-operating income (expense)	(63,113)	(59,600)	(189,590)	(161,185)	(220,222)	(181,889)	(116,164)
Income from continuing operations before income taxes	70,532	58,624	192,241	167,346	219,918	170,896	37,610
Provision for income taxes	(1,979)	(2,650)	(5,771)	(5,144)	(5,779)	(4,906)	(2,264)
Income from continuing operations	68,553	55,974	186,470	162,202	214,139	165,990	35,346
Income from discontinued operations	0	13,949	16,216	13,949	30,563	0	0
Net income	$ 68,553	$ 69,923	$ 202,686	$ 176,151	$ 244,702	$ 165,990	$ 35,346
Weighted average Operating Partnership units outstanding:
Basic (in shares)	292,867,986	266,139,175	290,661,305	266,125,252	266,131,712	249,451,258	232,181,070
Diluted (in shares)	293,025,483	266,335,914	290,865,862	266,308,393	266,319,797	249,634,668	232,430,401
Net income per Operating Partnership unit (basic) (in dollars per share)	$ 0.23	$ 0.26	$ 0.70	$ 0.66	$ 0.92	$ 0.67	$ 0.52
Net income per Operating Partnership unit (diluted) (in dollars per share)	0.23	0.26	0.70	0.66	0.92	0.66	0.52
MGP Operating Partnership | Continuing Operations
Weighted average Operating Partnership units outstanding:
Net income per Operating Partnership unit (basic) (in dollars per share)	0.23	0.21	0.64	0.61	0.80	0.67	0.52
Net income per Operating Partnership unit (diluted) (in dollars per share)	0.23	0.21	0.64	0.61	0.80	0.66	0.52
MGP Operating Partnership | Discontinued Operations
Weighted average Operating Partnership units outstanding:
Net income per Operating Partnership unit (basic) (in dollars per share)	0	0.05	0.06	0.05	0.12	0	0
Net income per Operating Partnership unit (diluted) (in dollars per share)	$ 0	$ 0.05	$ 0.06	$ 0.05	$ 0.12	$ 0	$ 0
Rental revenue
Revenues	$ 219,847	$ 186,564	$ 636,575	$ 559,690	$ 746,253	$ 675,089	$ 419,239
Rental revenue | MGP Operating Partnership
Revenues	219,847	186,564	636,575	559,690	746,253	675,089	419,239
Tenant reimbursements and other
Rental revenue					123,242	90,606	48,309
Revenues	6,164	30,095	18,618	93,198			48,309
Tenant reimbursements and other | MGP Operating Partnership
Revenues	$ 6,164	$ 30,095	$ 18,618	$ 93,198	$ 123,242	$ 90,606	$ 48,309

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Net income	$ 68,553	$ 69,923	$ 202,686	$ 176,151	$ 244,702	$ 165,990	$ 35,346
Other comprehensive income (loss)
Unrealized gain (loss) on cash flow hedges	(19,270)	4,736	(65,657)	27,372	4,128	9,782	1,879
Other comprehensive income (loss)	(19,270)	4,736	(65,657)	27,372	4,128	9,782	1,879
Comprehensive income (loss)	49,283	74,659	137,029	203,523	248,830	175,772	37,225
Less: Comprehensive income attributable to noncontrolling interests	(33,001)	(53,912)	(93,298)	(147,767)	(180,665)	(131,236)	(6,842)
Comprehensive income attributable to Class A shareholders	16,282	20,747	43,731	55,756	68,165	44,536	30,383
MGP Operating Partnership
Net income	68,553	69,923	202,686	176,151	244,702	165,990	35,346
Other comprehensive income (loss)
Unrealized gain (loss) on cash flow hedges	(19,270)	4,736	(65,657)	27,372	4,128	9,782	1,879
Other comprehensive income (loss)	(19,270)	4,736			4,128	9,782	1,879
Comprehensive income (loss)	$ 49,283	$ 74,659	$ 137,029	$ 203,523	$ 248,830	$ 175,772	$ 37,225

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended		12 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Cash flows from operating activities
Net income	$ 202,686	$ 176,151	$ 244,702	$ 165,990	$ 35,346
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Income from discontinued operations, net	(16,216)	(13,949)	(30,563)	0	0
Depreciation and amortization	223,062	199,933	266,622	260,455	220,667
Property transactions, net	11,344	18,851	20,319	34,022	4,684
Amortization of deferred financing costs and debt discount	9,602	9,391	12,031	11,360	7,195
Loss on retirement of debt	0	2,736	2,736	798	0
Amortization related to above market lease, net	0	514	686	686	286
Non-cash ground lease, net	778	514
Deemed contributions - tax sharing agreement	5,599	4,912	5,745	1,730	2,156
Straight-line rental revenues, excluding amortization of lease incentive asset	29,783	14,657	20,680	6,414	(1,739)
Amortization of lease incentive asset	11,355	0
Amortization of deferred revenue on non-normal tenant improvements	(1,636)	(2,762)	(3,711)	(2,352)	(80)
Share-based compensation	1,608	1,516	2,093	1,336	510
Deferred income taxes	(3,913)	2,848	5,090	3,176	108
Park MGM Transaction	(605,625)	0	2,801	0	0
Distributions received from discontinued operations and other	40,165	88
Changes in operating assets and liabilities:
Tenant and other receivables, net	(437)	550	(1,283)	3,118	(9,503)
Prepaid expenses and other assets	(222)	137	654	(1,537)	6,747
Due to MGM Resorts International and affiliates	71	(633)	(735)	796	166
Accounts payable, accrued expenses and other liabilities	(3,832)	67	5,403	158	5,101
Accrued interest	11,311	9,830	3,531	(3,572)	26,137
Net cash provided by (used in) operating activities	(84,517)	424,837	556,801	482,578	297,781
Cash flows from investing activities
Capital expenditures for property and equipment	0	(191)	(192)	(488)	(138,987)
Acquisition of Northfield	0	(1,068,337)	(1,068,336)	0	0
Proceeds from Northfield OpCo Transaction	3,779	0
MGM National Harbor Transaction			0	(462,500)	0
Net cash provided by (used in) investing activities	3,779	(1,068,528)	(1,068,528)	(462,988)	(138,987)
Cash flows from financing activities
Net borrowings (repayments) under bank credit facility	(566,813)	747,375	727,750	(41,875)	(16,750)
Proceeds from issuance of debt	750,000	0	0	350,000	3,700,000
Deferred financing costs	(9,983)	(17,490)	(17,490)	(5,598)	(77,163)
Repayment of assumed debt and bridge facilities	(245,950)	0	0	(425,000)	(4,544,850)
Issuance of Class A shares	699,362	0	0	404,685	1,207,500
Class A share issuance costs			0	(17,137)	(75,032)
Dividends and distributions paid	(395,005)	(337,865)	(454,260)	(385,435)	(150,829)
Net cash transfers from Parent			0	0	158,822
Other	(1,342)	0
Net cash provided by (used in) financing activities	230,269	392,020	256,000	(120,360)	201,698
Cash flows from discontinued operations, net
Cash flows provided by operating activities, net	15,591	8,250	23,406	0	0
Cash flows provided by (used in) investing activities, net	(12)	33,199	32,416	0	0
Cash flows used in financing activities, net	(37,900)	0	0	0	0
Net cash provided by (used in) discontinued operations	(22,321)	41,449	55,822	0	0
Change in cash and cash equivalents classified as assets held for sale	(22,321)	41,449	55,822	0	0
Cash and cash equivalents
Net increase (decrease) for the period	149,531	(251,671)	(255,727)	(100,770)	360,492
Balance, beginning of period	3,995	259,722	259,722	360,492	0
Balance, end of period	153,526	8,051	3,995	259,722	360,492
Supplemental cash flow disclosures
Interest paid	169,646	137,623	199,429	176,033	82,880
Non-cash investing and financing activities
Non-Normal Tenant Improvements by Tenant	0	18,172	19,316	52,995	72,402
Accrual of dividend and distribution payable to Class A shareholders and Operating Partnership unit holders	138,730	116,395	119,055	111,733	94,109
MGP Operating Partnership
Cash flows from operating activities
Net income	202,686	176,151	244,702	165,990	35,346
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Income from discontinued operations, net	(16,216)	(13,949)	(30,563)	0	0
Depreciation and amortization	223,062	199,933	266,622	260,455	220,667
Property transactions, net	11,344	18,851	20,319	34,022	4,684
Amortization of deferred financing costs and debt discount	9,602	9,391	12,031	11,360	7,195
Loss on retirement of debt	0	2,736	2,736	798	0
Amortization related to above market lease, net	0	514	686	686	286
Non-cash ground lease, net	778	514
Deemed contributions - tax sharing agreement	5,599	4,912	5,745	1,730	2,156
Straight-line rental revenues, excluding amortization of lease incentive asset	29,783	14,657	20,680	6,414	(1,739)
Amortization of lease incentive asset	11,355	0
Amortization of deferred revenue on non-normal tenant improvements	(1,636)	(2,762)	(3,711)	(2,352)	(80)
Share-based compensation	1,608	1,516	2,093	1,336	510
Deferred income taxes	(3,913)	2,848	5,090	3,176	108
Park MGM Transaction	(605,625)	0	2,801	0	0
Distributions received from discontinued operations and other	40,165	88
Changes in operating assets and liabilities:
Tenant and other receivables, net	(437)	550	(1,283)	3,118	(9,503)
Prepaid expenses and other assets	(222)	137	654	(1,537)	6,747
Due to MGM Resorts International and affiliates	71	(633)	(735)	796	166
Accounts payable, accrued expenses and other liabilities	(3,832)	67	5,403	158	5,101
Accrued interest	11,311	9,830	3,531	(3,572)	26,137
Net cash provided by (used in) operating activities	(84,517)	424,837	556,801	482,578	297,781
Cash flows from investing activities
Capital expenditures for property and equipment	0	(191)	(192)	(488)	(138,987)
Acquisition of Northfield	0	(1,068,337)	(1,068,336)	0	0
Proceeds from Northfield OpCo Transaction	3,779	0
MGM National Harbor Transaction			0	(462,500)	0
Net cash provided by (used in) investing activities	3,779	(1,068,528)	(1,068,528)	(462,988)	(138,987)
Cash flows from financing activities
Net borrowings (repayments) under bank credit facility	(566,813)	747,375	727,750	(41,875)	(16,750)
Proceeds from issuance of debt	750,000	0	0	350,000	3,700,000
Deferred financing costs	(9,983)	(17,490)	(17,490)	(5,598)	(77,163)
Repayment of assumed debt and bridge facilities	(245,950)	0	0	(425,000)	(4,544,850)
Issuance of Class A shares	699,362	0	0	387,548	1,132,468
Dividends and distributions paid	(395,005)	(337,865)	(454,260)	(385,435)	(150,829)
Net cash transfers from Parent			0	0	158,822
Other	(1,342)	0
Net cash provided by (used in) financing activities	230,269	392,020	256,000	(120,360)	201,698
Cash flows from discontinued operations, net
Cash flows provided by operating activities, net	15,591	8,250	23,406	0	0
Cash flows provided by (used in) investing activities, net	(12)	33,199	32,416	0	0
Cash flows used in financing activities, net	(37,900)	0	0	0	0
Net cash provided by (used in) discontinued operations	(22,321)	41,449	55,822	0	0
Change in cash and cash equivalents classified as assets held for sale	(22,321)	41,449	55,822	0	0
Cash and cash equivalents
Net increase (decrease) for the period	149,531	(251,671)	(255,727)	(100,770)	360,492
Balance, beginning of period	3,995	259,722	259,722	360,492	0
Balance, end of period	153,526	8,051	3,995	259,722	360,492
Supplemental cash flow disclosures
Interest paid	169,646	137,623	199,429	176,033	82,880
Non-cash investing and financing activities
Non-Normal Tenant Improvements by Tenant	0	18,172	19,316	52,995	72,402
Accrual of dividend and distribution payable to Class A shareholders and Operating Partnership unit holders	138,730	116,395	119,055	111,733	94,109
Northfield OpCo
Non-cash investing and financing activities
Redemption of Operating Partnership units relating to Northfield OpCo Transaction	301,373	0
Northfield OpCo | MGP Operating Partnership
Non-cash investing and financing activities
Redemption of Operating Partnership units relating to Northfield OpCo Transaction	301,373	0
Empire City
Non-cash investing and financing activities
Net assets acquired	625,000	0
Empire City | MGP Operating Partnership
Non-cash investing and financing activities
Net assets acquired	$ 625,000	$ 0
MGM National Harbor Transaction
Non-cash investing and financing activities
Net assets acquired			0	721,409	0
MGM National Harbor Transaction | MGP Operating Partnership
Non-cash investing and financing activities
Net assets acquired			0	721,409	0
Borgata
Non-cash investing and financing activities
Net assets acquired			0	0	1,273,230
Borgata | MGP Operating Partnership
Non-cash investing and financing activities
Net assets acquired			$ 0	$ 0	$ 1,273,230

Condensed Consolidated Statem_4

Condensed Consolidated Statements of Shareholders' Equity - USD ($)	Total	Common stock	Additional Paid-in Capital	Accumulated Deficit	Accumulated Other Comprehensive Income (Loss)	Predecessor Net Parent Investment	Total Class A Shareholders' Equity	Non-controlling Interest	Empire City	Empire CityAdditional Paid-in Capital	Empire CityAccumulated Other Comprehensive Income (Loss)	Empire CityTotal Class A Shareholders' Equity	Empire CityNon-controlling Interest	Park MGM Lease Transaction	Park MGM Lease TransactionAdditional Paid-in Capital	Park MGM Lease TransactionAccumulated Other Comprehensive Income (Loss)	Park MGM Lease TransactionTotal Class A Shareholders' Equity	Park MGM Lease TransactionNon-controlling Interest
Balance (in shares) at Dec. 31, 2015		0
Balance at Dec. 31, 2015	$ 6,058,959,000		$ 0	$ 0	$ 0	$ 6,058,959,000	$ 6,058,959,000	$ 0
Changes in equity:
Net income	(84,383,000)		0	0	0	(84,383,000)	(84,383,000)	0
Assumption of bridge facilities from MGM	(4,000,000,000)		0	0	0	(4,000,000,000)	(4,000,000,000)	0
Other contributions from MGM	1,893,502,000		0	0	0	1,893,502,000	1,893,502,000	0
Issuance of Class A shares (in shares)		0
Issuance of Class A shares	1,207,500,000		1,207,500,000	0	0	0	1,207,500,000	0
Initial public offering costs	(75,032,000)		(75,032,000)	0	0	0	(75,032,000)	0
Balance (in shares) at Dec. 31, 2015		0
Balance at Dec. 31, 2015	6,058,959,000		0	0	0	6,058,959,000	6,058,959,000	0
Changes in equity:
Net income	35,346,000
Acquisition Transaction	728,379,000		28,753,000	0	0	0	28,753,000	699,626,000
Northfield OpCo Transaction	0
Other comprehensive income - cash flow hedges	1,879,000
Balance (in shares) at Dec. 31, 2016		0
Balance at Dec. 31, 2016	5,608,261,000		1,363,130,000	(29,758,000)	445,000	0	1,333,817,000	4,274,444,000
Changes in equity:
Dividends declared	1.0382
Noncontrolling interest and additional paid-in capital	0	$ 0	201,785,000	0	0	(3,868,078,000)	(3,666,293,000)	3,666,293,000
Net income	119,729,000		0	29,938,000	0	0	29,938,000	89,791,000
Deemed contribution - tax sharing agreement	2,156,000		0	0	0	0	0	2,156,000
Dividends and distributions declared	(244,938,000)		0	(59,696,000)	0	0	(59,696,000)	(185,242,000)
Share-based compensation (shares)		0
Share-based compensation	510,000		124,000	0	0	0	124,000	386,000
Other comprehensive income - cash flow hedges	1,879,000		0	0	445,000	0	445,000	1,434,000
Balance (in shares) at Dec. 31, 2016		0
Balance at Dec. 31, 2016	5,608,261,000		1,363,130,000	(29,758,000)	445,000	0	1,333,817,000	4,274,444,000
Changes in equity:
Net income	165,990,000		0	41,775,000	0	0	41,775,000	124,215,000
Acquisition Transaction	296,409,000		19,372,000	0	11,000	0	19,383,000	277,026,000
Deemed contribution - tax sharing agreement	1,730,000		0	0	0	0	0	1,730,000
Dividends and distributions declared	(403,059,000)		0	(102,840,000)	0	0	(102,840,000)	(300,219,000)
Issuance of Class A shares (in shares)		0
Issuance of Class A shares	387,548,000		333,742,000	(4,125,000)	(109,000)	0	329,508,000	58,040,000
Share-based compensation (shares)		0
Share-based compensation	1,336,000		334,000	0	0	0	334,000	1,002,000
Northfield OpCo Transaction	0
Other comprehensive income - cash flow hedges	9,782,000		0	0	2,761,000	0	2,761,000	7,021,000
Other (shares)		0
Other	$ (258,000)		(88,000)	0	0	0	(88,000)	(170,000)
Balance (in shares) at Dec. 31, 2017	70,896,795	0
Balance at Dec. 31, 2017	$ 6,067,739,000	$ 0	1,716,490,000	(94,948,000)	3,108,000	0	1,624,650,000	4,443,089,000
Changes in equity:
Dividends declared	1.5975
Noncontrolling interest and additional paid-in capital	4,443,089,000
Net income	58,169,000			15,830,000			15,830,000	42,339,000
Deemed contribution - tax sharing agreement	1,231,000						0	1,231,000
Dividends and distributions declared	(111,733,000)			(29,777,000)			(29,777,000)	(81,956,000)
Share-based compensation	384,000		102,000				102,000	282,000
Other comprehensive income - cash flow hedges	16,355,000				4,358,000		4,358,000	11,997,000
Other	401,000		108,000				108,000	293,000
Balance (in shares) at Mar. 31, 2018		70,897,000
Balance at Mar. 31, 2018	6,032,546,000	$ 0	1,716,700,000	(108,895,000)	7,466,000		1,615,271,000	4,417,275,000
Changes in equity:
Dividends declared	$ 0.4200
Balance (in shares) at Dec. 31, 2017	70,896,795	0
Balance at Dec. 31, 2017	$ 6,067,739,000	$ 0	1,716,490,000	(94,948,000)	3,108,000	0	1,624,650,000	4,443,089,000
Changes in equity:
Net income	176,151,000
Northfield OpCo Transaction	(1,068,337,000)
Other comprehensive income - cash flow hedges	27,372,000
Balance (in shares) at Sep. 30, 2018		70,911,000
Balance at Sep. 30, 2018	$ 5,915,203,000	$ 0	1,711,813,000	(137,781,000)	10,404,000		1,584,436,000	4,330,767,000
Balance (in shares) at Dec. 31, 2017	70,896,795	0
Balance at Dec. 31, 2017	$ 6,067,739,000	$ 0	1,716,490,000	(94,948,000)	3,108,000	0	1,624,650,000	4,443,089,000
Changes in equity:
Net income	244,702,000		0	67,065,000	0	0	67,065,000	177,637,000
Deemed contribution - tax sharing agreement	5,745,000		0	0	0	0	0	5,745,000
Dividends and distributions declared	(461,582,000)		0	(123,025,000)	0	0	(123,025,000)	(338,557,000)
Share-based compensation (shares)		0
Share-based compensation	2,093,000		558,000	0	0	0	558,000	1,535,000
Northfield OpCo Transaction	(1,068,336,000)
Other comprehensive income - cash flow hedges	4,128,000		0	0	1,100,000	0	1,100,000	3,028,000
Other (shares)		0
Other	$ (17,319,000)		(4,377,000)	0	0	0	(4,377,000)	(12,942,000)
Balance (in shares) at Dec. 31, 2018	70,911,166	70,911,000
Balance at Dec. 31, 2018	$ 5,845,506,000	$ 0	1,712,671,000	(150,908,000)	4,208,000	0	1,565,971,000	4,279,535,000
Changes in equity:
Dividends declared	1.7350
Balance (in shares) at Mar. 31, 2018		70,897,000
Balance at Mar. 31, 2018	6,032,546,000	$ 0	1,716,700,000	(108,895,000)	7,466,000		1,615,271,000	4,417,275,000
Changes in equity:
Net income	48,059,000			13,146,000			13,146,000	34,913,000
Deemed contribution - tax sharing agreement	1,263,000						0	1,263,000
Dividends and distributions declared	(114,399,000)			(30,492,000)			(30,492,000)	(83,907,000)
Share-based compensation	556,000		149,000				149,000	407,000
Other comprehensive income - cash flow hedges	6,281,000				1,675,000		1,675,000	4,606,000
Other (shares)		14,000
Other	(3,000)		237,000				237,000	(240,000)
Balance (in shares) at Jun. 30, 2018		70,911,000
Balance at Jun. 30, 2018	5,974,303,000	$ 0	1,717,086,000	(126,241,000)	9,141,000		1,599,986,000	4,374,317,000
Changes in equity:
Dividends declared	0.4300
Net income	69,923,000			19,484,000			19,484,000	50,439,000
Deemed contribution - tax sharing agreement	2,418,000						0	2,418,000
Dividends and distributions declared	(116,395,000)			(31,024,000)			(31,024,000)	(85,371,000)
Share-based compensation	576,000		153,000				153,000	423,000
Other comprehensive income - cash flow hedges	4,736,000				1,263,000		1,263,000	3,473,000
Other	(20,358,000)		(5,426,000)				(5,426,000)	(14,932,000)
Balance (in shares) at Sep. 30, 2018		70,911,000
Balance at Sep. 30, 2018	5,915,203,000	$ 0	1,711,813,000	(137,781,000)	10,404,000		1,584,436,000	4,330,767,000
Changes in equity:
Dividends declared	0.4375
Net income	$ 68,551,000
Balance (in shares) at Dec. 31, 2018	70,911,166	70,911,000
Balance at Dec. 31, 2018	$ 5,845,506,000	$ 0	1,712,671,000	(150,908,000)	4,208,000	0	1,565,971,000	4,279,535,000
Changes in equity:
Noncontrolling interest and additional paid-in capital	4,279,535,000
Net income	66,364,000			19,955,000			19,955,000	46,409,000
Acquisition Transaction									$ 379,050,000	$ 23,940,000	$ (195,000)	$ 23,745,000	$ 355,305,000	$ 31,875,000	$ 2,512,000	$ (16,000)	$ 2,496,000	$ 29,379,000
Deemed contribution - tax sharing agreement	1,345,000						0	1,345,000
Dividends and distributions declared	(139,279,000)			(42,064,000)			(42,064,000)	(97,215,000)
Issuance of Class A shares (in shares)		19,550,000
Issuance of Class A shares	548,391,000		471,647,000		774,000		472,421,000	75,970,000
Share-based compensation	565,000		164,000				164,000	401,000
Other comprehensive income - cash flow hedges	(15,612,000)				(4,717,000)		(4,717,000)	(10,895,000)
Other	(1,288,000)		(389,000)				(389,000)	(899,000)
Balance (in shares) at Mar. 31, 2019		90,461,000
Balance at Mar. 31, 2019	6,716,917,000	$ 0	2,210,545,000	(173,017,000)	54,000		2,037,582,000	4,679,335,000
Changes in equity:
Dividends declared	$ 0.4650
Balance (in shares) at Dec. 31, 2018	70,911,166	70,911,000
Balance at Dec. 31, 2018	$ 5,845,506,000	$ 0	1,712,671,000	(150,908,000)	4,208,000	$ 0	1,565,971,000	4,279,535,000
Changes in equity:
Net income	202,686,000
Northfield OpCo Transaction	0
Other comprehensive income - cash flow hedges	$ (65,657,000)
Balance (in shares) at Sep. 30, 2019	95,468,067	95,468,000
Balance at Sep. 30, 2019	$ 6,384,304,000	$ 0	2,307,463,000	(216,824,000)	(16,129,000)		2,074,510,000	4,309,794,000
Balance (in shares) at Mar. 31, 2019		90,461,000
Balance at Mar. 31, 2019	6,716,917,000	$ 0	2,210,545,000	(173,017,000)	54,000		2,037,582,000	4,679,335,000
Changes in equity:
Net income	67,769,000			21,858,000			21,858,000	45,911,000
Deemed contribution - tax sharing agreement	2,275,000						0	2,275,000
Dividends and distributions declared	(136,671,000)			(43,310,000)			(43,310,000)	(93,361,000)
Issuance of Class A shares (in shares)		2,101,000
Issuance of Class A shares	64,908,000		52,294,000		(105,000)		52,189,000	12,719,000
Share-based compensation (shares)		77,000
Share-based compensation	524,000		164,000				164,000	360,000
Northfield OpCo Transaction	(298,957,000)		(27,441,000)	0	2,000		(27,439,000)	(271,518,000)
Other comprehensive income - cash flow hedges	(30,775,000)				(9,647,000)		(9,647,000)	(21,128,000)
Other	542,000		1,823,000				1,823,000	(1,281,000)
Balance (in shares) at Jun. 30, 2019		92,639,000
Balance at Jun. 30, 2019	6,386,532,000	$ 0	2,237,385,000	(194,469,000)	(9,696,000)		2,033,220,000	4,353,312,000
Changes in equity:
Dividends declared	0.4675
Net income	68,553,000			22,515,000			22,515,000	46,038,000
Deemed contribution - tax sharing agreement	1,979,000							1,979,000
Dividends and distributions declared	(138,730,000)			(44,870,000)			(44,870,000)	(93,860,000)
Issuance of Class A shares (in shares)		2,829,000
Issuance of Class A shares	86,063,000		70,338,000		(200,000)		70,138,000	15,925,000
Share-based compensation	519,000		166,000				166,000	353,000
Other comprehensive income - cash flow hedges	(19,270,000)				(6,233,000)		(6,233,000)	(13,037,000)
Other	$ (1,342,000)		(426,000)				(426,000)	(916,000)
Balance (in shares) at Sep. 30, 2019	95,468,067	95,468,000
Balance at Sep. 30, 2019	$ 6,384,304,000	$ 0	$ 2,307,463,000	$ (216,824,000)	$ (16,129,000)		$ 2,074,510,000	$ 4,309,794,000
Changes in equity:
Dividends declared	0.4700
Noncontrolling interest and additional paid-in capital	$ 4,309,794,000

Condensed Consolidated Statem_5

Condensed Consolidated Statements of Partners' Capital - USD ($) $ in Thousands	Total	MGP Operating Partnership	MGP Operating PartnershipPredecessor Net Parent Investment	MGP Operating PartnershipGeneral Partner	MGP Operating PartnershipLimited Partners	Empire City CasinoMGP Operating Partnership	Empire City CasinoMGP Operating PartnershipLimited Partners	Park MGM Lease TransactionMGP Operating Partnership	Park MGM Lease TransactionMGP Operating PartnershipLimited Partners
Changes in partners' capital:
Noncontrolling interest and additional paid-in capital	$ 6,058,959
Beginning balance at Dec. 31, 2015		$ 6,058,959	$ 6,058,959	$ 0	$ 0
Changes in partners' capital:
Net income	(84,383)	(84,383)	(84,383)	0	0
Assumption of bridge facilities from MGM	(4,000,000)	(4,000,000)	(4,000,000)	0	0
Other contributions from MGM	1,893,502	1,893,502	1,893,502	0	0
Issuance of Class A shares	1,207,500
Beginning balance at Dec. 31, 2015		6,058,959	6,058,959	0	0
Changes in partners' capital:
Net income	35,346	35,346	0	0	119,729
Deemed contribution - tax sharing agreement		2,156	0	0	2,156
Dividends and distributions declared		(244,938)	0	0	(244,938)
Issuance of Operating Partnership units		1,132,468	0	0	1,132,468
Acquisitions		728,379	0	0	728,379
Share-based compensation		510	0	0	510
Other comprehensive income - cash flow hedges	1,879	1,879	0	0	1,879
Ending balance at Dec. 31, 2016		5,608,261	0	0	5,608,261
Changes in partners' capital:
Noncontrolling interest and additional paid-in capital		0	(3,868,078)	0	3,868,078
Net income	119,729	119,729
Deemed contribution - tax sharing agreement	2,156
Share-based compensation	510
Other comprehensive income - cash flow hedges	1,879
Ending balance at Dec. 31, 2016		5,608,261	0	0	5,608,261
Changes in partners' capital:
Noncontrolling interest and additional paid-in capital	5,608,261
Net income	165,990	165,990	0	0	165,990
Deemed contribution - tax sharing agreement	1,730	1,730	0	0	1,730
Dividends and distributions declared		(403,059)	0	0	(403,059)
Issuance of Operating Partnership units		387,548	0	0	387,548
Acquisitions		296,409	0	0	296,409
Issuance of Class A shares	387,548
Share-based compensation	1,336	1,336	0	0	1,336
Other comprehensive income - cash flow hedges	9,782	9,782	0	0	9,782
Other		(258)	0	0	(258)
Ending balance at Dec. 31, 2017		6,067,739	0	0	6,067,739
Changes in partners' capital:
Noncontrolling interest and additional paid-in capital	6,067,739
Net income	58,169	58,169			58,169
Deemed contribution - tax sharing agreement	1,231	1,231			1,231
Dividends and distributions declared		(111,733)			(111,733)
Share-based compensation	384	384			384
Other comprehensive income - cash flow hedges	16,355	16,355			16,355
Other		401			401
Ending balance at Mar. 31, 2018		6,032,546		0	6,032,546
Beginning balance at Dec. 31, 2017		6,067,739	0	0	6,067,739
Changes in partners' capital:
Net income	176,151	176,151
Other comprehensive income - cash flow hedges	27,372
Ending balance at Sep. 30, 2018		5,915,203		0	5,915,203
Beginning balance at Dec. 31, 2017		6,067,739	0	0	6,067,739
Changes in partners' capital:
Net income	244,702	244,702	0	0	244,702
Deemed contribution - tax sharing agreement	5,745	5,745	0	0	5,745
Dividends and distributions declared		(461,582)	0	0	(461,582)
Share-based compensation	2,093	2,093	0	0	2,093
Other comprehensive income - cash flow hedges	4,128	4,128	0	0	4,128
Other		(17,319)	0	0	(17,319)
Ending balance at Dec. 31, 2018		5,845,506	0	0	5,845,506
Changes in partners' capital:
Noncontrolling interest and additional paid-in capital	6,032,546
Beginning balance at Mar. 31, 2018		6,032,546		0	6,032,546
Changes in partners' capital:
Net income	48,059	48,059			48,059
Deemed contribution - tax sharing agreement	1,263	1,263			1,263
Dividends and distributions declared		(114,399)			(114,399)
Share-based compensation	556	556			556
Other comprehensive income - cash flow hedges	6,281	6,281			6,281
Other		(3)			(3)
Ending balance at Jun. 30, 2018		5,974,303		0	5,974,303
Changes in partners' capital:
Noncontrolling interest and additional paid-in capital	5,974,303
Net income	69,923	69,923			69,923
Deemed contribution - tax sharing agreement	2,418	2,418			2,418
Dividends and distributions declared		(116,395)			(116,395)
Share-based compensation	576	576			576
Other comprehensive income - cash flow hedges	4,736	4,736			4,736
Other		(20,358)			(20,358)
Ending balance at Sep. 30, 2018		5,915,203		0	5,915,203
Changes in partners' capital:
Noncontrolling interest and additional paid-in capital	5,915,203
Net income	68,551	68,551
Ending balance at Dec. 31, 2018		5,845,506	0	0	5,845,506
Changes in partners' capital:
Noncontrolling interest and additional paid-in capital	5,845,506
Net income	66,364	66,364			66,364
Deemed contribution - tax sharing agreement	1,345	1,345			1,345
Dividends and distributions declared		(139,279)			(139,279)
Issuance of Operating Partnership units		548,391			548,391
Acquisitions						$ 379,050	$ 379,050	$ 31,875	$ 31,875
Issuance of Class A shares	548,391
Share-based compensation	565	565			565
Other comprehensive income - cash flow hedges	(15,612)	(15,612)			(15,612)
Other		(1,288)			(1,288)
Ending balance at Mar. 31, 2019		6,716,917		0	6,716,917
Beginning balance at Dec. 31, 2018		5,845,506	$ 0	0	5,845,506
Changes in partners' capital:
Net income	202,686	202,686
Other comprehensive income - cash flow hedges	(65,657)
Ending balance at Sep. 30, 2019		6,384,304		0	6,384,304
Changes in partners' capital:
Noncontrolling interest and additional paid-in capital	6,716,917
Beginning balance at Mar. 31, 2019		6,716,917		0	6,716,917
Changes in partners' capital:
Net income	67,769	67,769			67,769
Deemed contribution - tax sharing agreement	2,275	2,275			2,275
Dividends and distributions declared		(136,671)			(136,671)
Issuance of Class A shares	64,908	64,908			64,908
Share-based compensation	524	524			524
Other comprehensive income - cash flow hedges	(30,775)	(30,775)			(30,775)
Other		542			542
Northfield OpCo Transaction		(298,957)			(298,957)
Ending balance at Jun. 30, 2019		6,386,532		0	6,386,532
Changes in partners' capital:
Noncontrolling interest and additional paid-in capital	6,386,532
Net income	68,553	68,553			68,553
Deemed contribution - tax sharing agreement	1,979	1,979			1,979
Dividends and distributions declared		(138,730)			(138,730)
Issuance of Operating Partnership units		86,063			86,063
Issuance of Class A shares	86,063
Share-based compensation	519	519			519
Other comprehensive income - cash flow hedges	(19,270)	(19,270)			(19,270)
Other		(1,342)			(1,342)
Ending balance at Sep. 30, 2019		$ 6,384,304		$ 0	$ 6,384,304
Changes in partners' capital:
Noncontrolling interest and additional paid-in capital	$ 6,384,304

Business

Business	9 Months Ended	12 Months Ended
	Sep. 30, 2019	Dec. 31, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
BUSINESS	BUSINESS Organization. MGP is a publicly traded REIT primarily engaged through its investment in the Operating Partnership in the real property business, which consists of owning, acquiring and leasing large-scale destination entertainment and leisure properties, whose tenants generally offer casino gaming, hotel, convention, dining, entertainment and retail. A wholly owned subsidiary of the Operating Partnership (the “Landlord”) leases all of its real estate properties to a wholly owned subsidiary (the “Tenant”) of MGM Resorts International (“MGM”) under a master lease agreement (the “Master Lease”). As of September 30, 2019, there were approximately 295.2 million Operating Partnership units outstanding in the Operating Partnership, of which MGM owned approximately 199.7 million, or 67.7%, and MGP owned the remaining 32.3%. MGM’s Operating Partnership units are exchangeable for Class A shares of MGP on a one​​​​​​​ non-economic Empire City Transaction On January 29, 2019, the Company acquired the developed real property associated with Empire City Casino (“Empire City”) from MGM upon its acquisition of Empire City (“Empire City Transaction”) and Empire City was added to the existing Master Lease between the Landlord and Tenant. Refer to Note 3 for additional details on the Empire City Transaction and Note 5 for further discussion on the Master Lease. Park MGM Transaction On March 7, 2019, the Company completed the transaction relating to renovations undertaken by MGM Resorts regarding the Park MGM and NoMad Las Vegas property (the “Park MGM Transaction”). Refer to Note 5 for further discussion on the Master Lease. Northfield OpCo Transaction On April 1, 2019, the Company transferred the membership interests of Northfield Park Associates, LLC (“Northfield”), the entity that formerly owned the real estate assets and operations of the Hard Rock Rocksino Northfield Park in Northfield, Ohio, to a subsidiary of MGM and the Company retained the real estate assets. The Company’s taxable REIT subsidiary (“TRS”) that owned Northfield liquidated immediately prior to the transfer. Subsequently, MGM rebranded the operations it acquired (“Northfield OpCo”) to MGM Northfield Park, which was added to the existing Master Lease between the Landlord and Tenant. Refer to Note 3 for additional details on the Northfield OpCo Transaction and Note 5 for further discussion on the Master Lease.	BUSINESS Organization. MGM Resorts International (“MGM” or the “Parent”) is a Delaware corporation that acts largely as a holding company and, through its subsidiaries, owns and operates large-scale destination entertainment and leisure resorts. Prior to the IPO Date, the real estate assets of The Mirage, Mandalay Bay, Luxor, New York-New On the IPO Date, MGP completed the initial public offering of 57.5 million of its Class A shares representing limited liability company interests. MGP contributed the proceeds from its initial public offering to the Operating Partnership in exchange for 26.7% of the Operating Partnership units and the general partner interest in the Operating Partnership. Certain subsidiaries of MGM acquired the remaining 73.3% of the outstanding Operating Partnership units on such date. MGM retained ownership of MGP’s outstanding Class B share. The Class B share is a non-economic As discussed in Note 3 and Note 9, the Operating Partnership issued additional Operating Partnership units in connection with the Borgata Transaction, follow-on units are exchangeable into Class A shares of MGP on a one-to-one MGP is a publicly traded REIT primarily engaged through its investment in the Operating Partnership in the real property business, which consists of owning, acquiring and leasing large-scale destination entertainment and leisure resorts, whose tenants generally offer casino gaming, hotel, convention, dining, entertainment and retail. A wholly owned subsidiary of the Operating Partnership (the “Landlord”) leases all of its real estate properties back to a wholly owned subsidiary of MGM (the “Tenant”) under a master lease agreement (the “Master Lease”). Northfield Acquisition and Northfield OpCo Transaction On July 6, 2018, a wholly owned taxable REIT subsidiary of the Company (the “TRS”) completed its previously announced acquisition of the membership interests of Northfield Park Associates, LLC (“Northfield”), an Ohio limited liability company that owned the real estate assets and operations of the Hard Rock Rocksino Northfield Park (the “Rocksino” and such acquisition the “Northfield Acquisition”) from Milstein Entertainment LLC. Simultaneously with the close of the transaction, Northfield entered into a new agreement with an affiliate of Hard Rock Café International (STP), Inc. (“Hard Rock”) to continue to serve as the manager of the property. Refer to Note 2 and Note 3 for additional details. On April 1, 2019, the TRS liquidated. Concurrently, a subsidiary of MGM acquired the membership interests of Northfield for consideration consisting primarily of Operating Partnership units that were ultimately redeemed by the Operating Partnership, and the Company retained the real estate assets (collectively, the “Northfield OpCo Transaction”). Refer to Note 3 for additional details on the Northfield OpCo Transaction and the presentation of discontinued operations. Empire City Transaction On January 29, 2019, the Company acquired the real property associated with the Empire City Casino’s race track and casino (“Empire City”) from MGM upon its acquisition of Empire City for fair value of consideration transferred of approximately $634 million, which included the assumption of approximately $246 million of debt by the Operating Partnership with the balance through the issuance of 12.9 million​​​​​​​ Operating Partnership units to MGM (“Empire City Transaction”). Empire City was added to the existing Master Lease between the Landlord and Tenant. As a result, the annual rent payment to MGP increased by $50 million, prorated for the remainder of the lease year. Consistent with the Master Lease terms, 90% of this rent will be fixed and contractually grow at 2​​​​​​​% per year until 2022. In addition, pursuant to the Master Lease, MGP has a right of first offer with respect to certain undeveloped land adjacent to the property to the extent MGM develops additional gaming facilities and chooses to sell or transfer the property in the future. Park MGM Lease Transaction On December 20, 2018, the Company entered into a definitive agreement with MGM whereby the Company will pay MGM consideration of $637.5 million for renovations undertaken by MGM regarding the Park MGM and NoMad Las Vegas property (the “Park MGM Lease Transaction”). Additionally, at closing the parties will enter into an amendment to the Master Lease whereby the annual rent payment to the Company will increase by $50.0 million, prorated for the remainder of the lease year. Consistent with the Master Lease terms, 90% of this rent will be fixed and contractually grow at 2% per year until 2022. The transaction is expected to close in the first quarter of 2019 and is subject to customary closing conditions. Segments The Company’s TRS liquidated in connection with the Northfield OpCo Transaction in April 2019 and, accordingly, the Company solely generates revenue from its real estate properties.

Basis of Presentation and Summa

Basis of Presentation and Summary of Significant Accounting Policies	9 Months Ended	12 Months Ended
	Sep. 30, 2019	Dec. 31, 2018
Accounting Policies [Abstract]
BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Basis of presentation. The accompanying condensed consolidated financial statements and related notes should be read in conjunction with the audited financial statements and notes thereto included in the Company’s most recent Annual Report on Form 10-K. Variable Interest Entities. Noncontrolling interest. MGM may tender its Operating Partnership units for redemption by the Operating Partnership in exchange for cash equal to the market price of MGP’s Class A shares at the time of redemption or for unregistered Class A shares on a one Fair value measurements. paid to transfer a liability in an orderly transaction between market participants at the measurement date and is measured according to a hierarchy that includes: Level 1 inputs, such as quoted prices in an active market; Level 2 inputs, which are observable inputs for similar assets; or Level 3 inputs, which are unobservable inputs. The Company used the following inputs in its fair value measurements: • Level 2 inputs for its long-term debt fair value disclosures. See Note 6; and • Level 2 inputs when measuring the fair value of its interest rate swaps. See Note 7. Real estate investments. Although the Tenant is responsible for all capital expenditures during the term of the Master Lease, if, in the future, a deconsolidation event occurs, the Company will be required to pay the Tenant, should the Tenant so elect, for certain capital improvements that would not constitute “normal tenant improvements” in accordance with U.S. GAAP (“Non-Normal the 10-year Treasury 600 Non-Normal Non-Normal Lease incentive asset. Non-Normal Deferred revenue. Non-Normal Non-Normal Ground lease and other reimbursable expenses. triple-net Revenue recognition. non-cancelable ten years four five be fixed and measurable. The difference between such rental revenue earned and the cash paid under the provisions of the Master Lease is recorded as deferred rent receivable and included as a component of tenant and other receivables, net or as deferred revenue if cash rent due exceeds rental revenue earned. Tenant reimbursement revenue and other reflects the amortization of deferred revenue relating to Non-Normal non-cash Lessee leases. For leases with terms greater than twelve months, the operating lease right-of-use Reportable segment. Income tax provision. year-to-date The Company accounts for income taxes under the asset and liability method, which requires the recognition of deferred tax assets and liabilities for the expected future tax consequences of events that have been included in the financial statements. Under this method, the Company determines deferred tax assets and liabilities on the basis of the differences between the financial statement and tax basis of assets and liabilities by using enacted tax rates in effect for the year in which the differences are expected to reverse. The effect of a change in tax rates on deferred tax assets and liabilities is recognized in income in the period that includes the enactment date. The Landlord is required to join in the filing of a New Jersey consolidated corporation business tax return under the New Jersey Casino Control Act and include in such return its income and expenses associated with its New Jersey assets and is thus subject to an entity level tax in New Jersey. Although the consolidated New Jersey return also includes MGM and certain of its subsidiaries, the Company is required to record New Jersey state income taxes in the accompanying financial statements as if the Landlord was taxed for state purposes on a stand-alone basis. The Company and MGM have entered into a tax sharing agreement providing for an allocation of taxes due in the consolidated New Jersey return. Pursuant to this agreement, the Landlord will only be responsible for New Jersey taxes on any gain that may be realized upon a future sale of the New Jersey assets resulting solely from an appreciation in value of such assets over their value on the date they were contributed to the Landlord by a subsidiary of MGM. MGM is responsible for all other taxes reported in the New Jersey consolidated return and, accordingly, the related income tax balances related to such taxes is reflected within noncontrolling interest within the accompanying financial statements. No amounts were due to MGM under the tax sharing agreement as of September 30, 2019 and December 31, 2018. Prior to April 1, 2019, the Company’s TRS owned the real estate assets and operations of Northfield and the Company recorded a tax provision on the income from the TRS operations. In connection with the Northfield OpCo Transaction, the TRS was liquidated on April 1, 2019 and the Company transferred the Northfield operations to a subsidiary of MGM and the Company retained the real estate. Consequently, the Company does not provide a tax provision on TRS operations after April 1, 2019. Recently issued accounting standards. The Company is also a lessee in lease arrangements, primarily for land underlying certain of its properties. As a result of adoption, the Company recognized approximately $279.9 million of operating ROU assets and approximately $333.5 million of operating lease liabilities as of January 1, 2019.	BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES Basis of presentation. For periods prior to the IPO Date, the accompanying combined and consolidated financial statements of MGP and the Operating Partnership represent the IPO Properties, which were controlled by MGM, and have been determined to be MGP’s and the Operating Partnership’s predecessor for accounting purposes (the “Predecessor”). The accompanying combined and consolidated financial statements include Predecessor financial statements that have been “carved out” of MGM’s consolidated financial statements and reflect significant assumptions and allocations. The financial statements do not fully reflect what the Predecessor’s results of operations, financial position and cash flows would have been if the Predecessor had been a stand-alone company during the periods presented. As a result, historical financial information is not necessarily indicative of the future results of operations, financial position and cash flows of MGP or the Operating Partnership. For periods subsequent to the IPO Date, the accompanying combined and consolidated financial statements of MGP and the Operating Partnership represent the results of operations, financial positions and cash flows of MGP and the Operating Partnership, including their respective subsidiaries. Certain reclassifications have been made to conform the prior period presentation. Property tax expense and property insurance expense were separately classified in prior periods and now are classified within “reimbursable expenses” in the accompanying combined and consolidated statements of operations. Principles of consolidation. the exemption from providing certain of the required disclosures associated with investments in VIEs. The combined and consolidated financial statements of the Operating Partnership include the accounts of its wholly owned subsidiary, the Landlord, which owns the real estate, a VIE of which the Operating Partnership is the primary beneficiary. As of December 31, 2018, on a consolidated basis, the Landlord had total assets of $9.8 billion primarily related to its real estate assets and total liabilities of $247.5 million primarily related to its deferred revenue and above market lease liability. For entities not determined to be VIEs, the Company consolidates such entities in which the Company owns 100% of the equity. For entities in which the Company owns less than 100% of the equity interest, the Company consolidates the entity if it has the direct or indirect ability to control the entities’ activities based upon the terms of the respective entities’ ownership agreements. All intercompany balances and transactions are eliminated in consolidation. Noncontrolling interest. MGM may tender its Operating Partnership units for redemption by the Operating Partnership in exchange for cash equal to the market price of MGP’s Class A shares at the time of redemption or for unregistered Class A shares on a one Use of estimates. Real estate investments. Although the Tenant is responsible for all capital expenditures during the term of the Master Lease, if, in the future, a deconsolidation event occurs, the Company will be required to pay the Tenant, should the Tenant so elect, for certain capital improvements that would not constitute “normal tenant improvements” in accordance with U.S. GAAP (“Non-Normal receive additional rent based on the 10-year Treasury 600 Non-Normal Non-Normal Inception-to-date, Non-Normal Property and Equipment used in operations. The Company evaluates its long-lived assets for impairment based on its classification as held for sale or to be held and used. Several criteria must be met before an asset is classified as held for sale, including that management with the appropriate authority commits to a plan to sell the asset to a third-party at a reasonable price in relation to its fair value and is actively seeking a buyer. For assets held for sale, the Company recognizes the asset at the lower of carrying value or fair market value less costs to sell, as estimated based on comparable asset sales, offers received, or a discounted cash flow model. For assets to be held and used, the Company reviews for impairment whenever indicators of impairment exist. The Company then compares the estimated future cash flows of the asset, on an undiscounted basis, to the carrying value of the asset. If the undiscounted cash flows exceed the carrying value, no impairment is indicated. If the undiscounted cash flows do not exceed the carrying value, then an impairment charge is recorded based on the fair value of the asset, typically measured using a discounted cash flow model. All recognized impairment losses, whether for assets held for sale or assets to be held and used, are recorded as operating expenses. There were no Depreciation and property transactions. Buildings and building improvements 20 to 40 years Land improvements 10 to 20 years Furniture, fixtures and equipment 3 to 20 years Property transactions, net are comprised of transactions related to long-lived assets, such as normal losses on the disposition of assets. Cash and cash equivalents. Revenue recognition. non-cancelable ten years​​​​​​​ and all four five years​​​​​​​ Tenant reimbursement revenue arises from costs which the Company is the primary obligor that are required to be paid by the Tenant or reimbursed to the Company pursuant to the Master Lease. This revenue is recognized in the same periods as the expense is incurred. Northfield generates gaming, food, beverage and other revenue, which primarily consists of video lottery ​​​​​​​terminal (“VLT”) wager transactions and food and beverage transactions. The transaction price for a VLT wager is the difference between gaming wins and losses (net win). The Company accounts for VLT revenue on a portfolio basis given the similar characteristics of wagers by recognizing net win per gaming day versus on an individual wager basis. The transaction price of food and beverage contracts is the amount collected from customer or stand-alone selling price for such goods and services and is recorded when the delivery is made. Sales and usage-based taxes are excluded from revenues. Gaming, food, beverage and other revenue relate to the operations of Northfield and are classified as discontinued operations. Refer to Note 3 for further information. Deferred revenue. Non-Normal Non-Normal Goodwill and other intangible assets. No Accounting guidance provides entities the option to perform a qualitative assessment of goodwill and indefinite-lived intangible assets (commonly referred to as step zero) in order to determine whether further impairment testing is necessary. In performing the step zero analysis the Company considers macroeconomic conditions, industry and market considerations, current and forecasted financial performance, entity-specific events, and changes in the composition or carrying amount of net assets of reporting units for goodwill. In addition, the Company takes into consideration the amount of excess of fair value over carrying value determined in the last quantitative analysis that was performed, as well as the period of time that has passed since the last quantitative analysis. If the step zero analysis indicates that it is more likely than not that the fair value is less than its carrying amount, the entity would proceed to a quantitative analysis. Under the quantitative analysis, goodwill for relevant reporting units is tested for impairment using ​​​​​​​a discounted cash flow analysis based on the estimated future results of the Company’s reporting units discounted using market discount rates and market indicators of terminal year capitalization rates, and a market approach that utilizes business enterprise value multiples based on a range of multiples from the Company’s peer group. An impairment charge is recognized for the amount by which the carrying value exceeds the reporting unit’s fair value, not to exceed the total amount of goodwill allocated to that reporting unit. Under the qualitative analysis, the license rights are tested for impairment using a discounted cash flow approach. If the fair value of an indefinite-lived intangible asset is less than its carrying amount, an impairment loss is recognized equal to the difference. Reimbursable expenses. Acquisition-related expenses. General and administrative. Net income per share. Net income per unit. Deferred financing costs. Derivative financial instruments. Derivatives and Hedging Fair value measurements • Level 2 inputs for its long-term debt fair value disclosures. See Note 6; • Level 2 inputs when measuring the fair value of its interest rate swaps. See Note 7; and • Level 2 and Level 3 inputs when assessing the fair value of assets acquired and liabilities assumed during the Northfield Acquisition. See Note 3. Income taxes. been included in the financial statements. Under this method, the Company determines deferred tax assets and liabilities on the basis of the differences between the financial statement and tax bases of assets and liabilities by using enacted tax rates in effect for the ​​​​​​​year in which the differences are expected to reverse. The effect of a change in tax rates on deferred tax assets and liabilities is recognized in income in the period that includes the enactment date. Concentrations of credit risk. Geographical risk. Recently issued accounting standards. No. 2017-04, 2017-04”). 2017-04 2017-04 In August 2017, the FASB issued ASU No. 2017-12, Derivatives 2017-12”). 2017-12 2017-12 2017-12 In February 2018, the FASB issued ASC 842 “Leases (Topic 842),” which replaces the existing guidance in ASC 840, “Leases,” (“ASC 842”). ASC 842 is effective for fiscal years, and interim periods within those years, beginning after December 15, 2018. ASC 842 requires a dual approach for lessee accounting under which a lessee would account for leases as finance leases or operating leases. Both finance leases and operating leases will result in the lessee recognizing a right-of-use In May 2014, the FASB issued ASC 606, Revenue from Contracts with Customers (Topic 606) which outlines a new, single comprehensive model for entities to use in accounting for revenue arising from contracts with customers and supersedes most current revenue recognition guidance​​​​​​​, including industry-specific guidance. Under the standard, revenue is recognized when a customer obtains control of promised goods or services in an amount that reflects the consideration the entity expects to receive in exchange for those goods and services. The Company adopted ASC 606 on January 1, 2018 and it did not have a material​​​​​​​ impact on the Company’s financial statements.

Acquisitions and dispositions

Acquisitions and dispositions	9 Months Ended	12 Months Ended
	Sep. 30, 2019	Dec. 31, 2018
Business Combinations [Abstract]
Acquisitions and dispositions	ACQUISITIONS AND DISPOSITIONS Empire City Acquisition As discussed in Note 1, on January 29, 2019, the Company ​​​​​​​acquired the ​​​​​​​developed real property associated with Empire City from MGM for fair value consideration of approximately $634.4 million. The Company funded the acquisition of the developed real property from MGM through the assumption of approximately $246.0 million of indebtedness, which was repaid with borrowings under its senior secured credit facility, and the issuance of approximately 12.9 million Operating Partnership units to MGM. Empire City was added to the existing Master Lease between the Landlord and Tenant, as further discussed in Note 5. The Empire City Transaction was accounted for as a transaction between entities under common control and, therefore, the Company recorded the Empire City real estate assets at the carryover value of $625.0 million from MGM with the difference between the purchase price and carrying value of assets, which was approximately $9.4 million, recorded as a reduction to additional paid-in-capital. Northfield Acquisition and Northfield OpCo Transaction On July 6, 2018 the TRS completed its acquisition of 100% of the membership interests of Northfield for a purchase price of approximately $1.1 billion. The Company recognized 100% of the assets and liabilities of Northfield at fair value at the date of the acquisition. On April 1, 2019, the Company transferred Northfield OpCo to a subsidiary of MGM for fair value consideration of approximately $305.2 million consisting primarily of approximately 9.4 million Operating Partnership units that were ultimately redeemed by the Operating Partnership and the Company retained the real estate assets. The Company’s TRS that owned Northfield liquidated immediately prior to the transfer. Subsequently, MGM rebranded Northfield OpCo to MGM Northfield Park, which was then added to the existing Master Lease between the Landlord and Tenant. Refer to Note 5 for further discussion on the Master Lease. The Northfield OpCo Transaction was accounted for as a transaction between entities under common control and, therefore, the Company had carried the Northfield OpCo operating assets and liabilities as held and used until the close of the transaction on April 1, 2019. As a transaction between entities under common control, the Company recorded the difference between the purchase price of $305.2​​​​​​​ million and the carrying value of net assets transferred of $292.3 million to additional paid-in-capital. The Company’s results for Northfield OpCo for the three and nine months ended September 30, 2018 and the nine months ended September 30, 2019 are reflected in discontinued operations on the consolidated statement of operations and the related assets and liabilities have been reclassified as assets held for sale and liabilities related to assets held for sale on the consolidated balance sheet on a retrospective basis. The retained MGM Northfield Park real estate assets have been retrospectively reclassified into real estate investments, net. The major classes of assets and liabilities of the Northfield OpCo presented as assets and liabilities related to assets held for sale as of December 31, 2018 were as follows: December 31, 2018 (in thousands) Assets held for sale Property and equipment, used in operations, net $ 20,391 Cash and cash equivalents 55,822 Tenant and other receivables, net 7,322 Prepaid expenses and other assets 3,024 Goodwill 17,915 Other intangible assets, net 251,214 Assets held for sale $ 355,688 Liabilities related to assets held for sale Due to MGM Resorts International and affiliates $ 80 Accounts payable, accrued expenses and other liabilities 28,806 Deferred revenue 51 Liabilities related to assets held for sale $ 28,937 The results of the Northfield OpCo discontinued operations are summarized as follows: Nine Months Ended Three and Nine Months Ended 2019 (1) 2018 (2) Total revenues $ 67,841 $ 65,562 Total expenses (48,735 ) (48,997 ) Income from discontinued operations before income taxes 19,106 16,565 Provision for income taxes (2,890 ) (2,616 ) Income from discontinued operations, net of tax 16,216 13,949 Less: Income attributable to noncontrolling interests — discontinued operations (11,434 ) (10,231 ) Income from discontinued operations attributable to Class A shareholders $ 4,782 $ 3,718 (1) There was no income from discontinued operations for the three months ended September 30, 2019. (2) As Northfield was acquired on July 6, 2018, the results of the Northfield OpCo discontinued operations are the same for both the three and nine months ended September 30, 2018.	ACQUISITIONS AND DISPOSITIONS Northfield Acquisition and Northfield OpCo Transaction. The Company recognized 100% of the assets and liabilities of Northfield at fair value at the date of the acquisition. Under the acquisition method, the fair value was allocated to the assets acquired and liabilities assumed in the transaction. The allocation of fair value for substantially all of the assets and liabilities is preliminary and may be adjusted up to one year after the acquisition. Specifically, as of December 31, 2018, the Company was finalizing valuation work related to the asset classes that comprise the property and equipment acquired. The following table sets forth the preliminary purchase price allocation at July 6, 2018 (in thousands): Fair value of assets acquired and liabilities: Property and equipment used in operations $ 792,807 Cash and cash equivalents 35,831 Racing and gaming licenses 228,000 Customer list 25,000 Goodwill 17,915 Other assets 9,598 Other liabilities (38,786 ) $ 1,070,365 As discussed above, the Company recognized the identifiable intangible assets at fair value. The estimated fair values of the intangible assets were preliminarily determined using methodologies under the income approach based on significant inputs that were not observable. The goodwill is primarily attributable to the synergies expected to arise after the acquisition. Consolidated results. Northfield OpCo Transaction. The Northfield OpCo Transaction was accounted for as a transaction between entities under common control and, therefore, the Company had carried the Northfield OpCo operating assets and liabilities as held and used until the close of the transaction on April 1, 2019. The Company’s results for Northfield OpCo for the year ended December 31, 2018 are reflected in discontinued operations on the consolidated statement of operations and the related assets and liabilities have been reclassified as assets held for sale and liabilities related to assets held for sale on the consolidated balance sheet on a retrospective basis. The retained real estate assets have been retrospectively reclassified into real estate investments, net. The major classes of assets and liabilities of the Northfield OpCo presented as assets and liabilities related to assets held for sale as of December 31, 2018 were as follows: December 31, 2018 (In thousands) Assets held for sale Property and equipment, used in operations, net $ 20,391 Cash and cash equivalents 55,822 Tenant and other receivables, net 7,322 Prepaid expenses and other assets 3,024 Goodwill 17,915 Other intangible assets, net 251,214 Assets held for sale $ 355,688 Liabilities related to assets held for sale Due to MGM Resorts International and affiliates $ 80 Accounts payable, accrued expenses and other liabilities 28,806 Deferred revenue 51 Liabilities related to assets held for sale $ 28,937 The results of the Northfield OpCo discontinued operations are summarized as follows: Year Ended December 31, (In thousands) Total revenues $ 132,949 Total expenses (97,330 ) Income for discontinued operations before income taxes 35,619 Provision for income tax (5,056 ) Income from discontinued operations, net of tax 30,563 Less: Net income attributable to noncontrolling interests — discontinued operations (22,417 ) Net income from discontinued operations $ 8,146 MGM National Harbor Transaction. The MGM National Harbor Transaction was accounted for as a transaction between entities under common control, and therefore the Company recorded the MGM National Harbor real estate assets at the carryover value of $1.18 billion from MGM. In addition, the Operating Partnership was assigned ground leases for an approximate 23 acres underlying MGM National Harbor, which the terms extends through 2082. Under the terms of the Master Lease, the Tenant is responsible for the rent payments related to the ground leases during the term of the Master Lease. Borgata Transaction.

Real Estate Investments

Real Estate Investments	9 Months Ended	12 Months Ended
	Sep. 30, 2019	Dec. 31, 2018
Real Estate [Abstract]
REAL ESTATE INVESTMENTS	REAL ESTATE INVESTMENTS The carrying value of real estate investments is as follows: September 30, December 31, (in thousands) Land $ 4,631,013 $ 4,536,013 Buildings, building improvements, land improvements and integral equipment 9,281,926 8,782,321 13,912,939 13,318,334 Less: Accumulated depreciation (3,018,818 ) (2,812,205 ) $ 10,894,121 $ 10,506,129	REAL ESTATE INVESTMENTS The carrying value of real estate investments is as follows: December 31, 2018 2017 (in thousands) Land $ 4,536,013 $ 4,143,513 Buildings, building improvements, land improvements and integral equipment 8,782,321 8,512,334 13,318,334 12,655,847 Less: Accumulated depreciation (2,812,205 ) (2,633,909 ) $ 10,506,129 $ 10,021,938

Leases

Leases	9 Months Ended	12 Months Ended
	Sep. 30, 2019	Dec. 31, 2018
Leases [Abstract]
Leases	LEASES Master Lease. ten years four five ten-year ten-year On January 29, 2019, Empire City was added to the existing Master Lease between the Landlord and Tenant. As a result, the annual rent payment to MGP increased by $50 million, prorated for the remainder of the lease year. Consistent with the Master Lease terms, 90% of this rent is fixed and will contractually grow at 2% per year until 2022. In addition, pursuant to the Master Lease, MGP has a right of first offer with respect to certain undeveloped land adjacent to the property to the extent MGM develops additional gaming facilities and chooses to sell or transfer the property in the future. On March 7, 2019, the Company completed the Park MGM Transaction and amended the existing Master Lease between the Landlord and Tenant concurrent with which the Company paid $637.5 million, of which $605.6 million was cash and the remainder was the issuance of approximately 1.0 million of Operating Partnership units, to a subsidiary of MGM and, as a result, the annual rent payment to the Company increased by $50 million, prorated for the remainder of the lease year. Consistent with the Master Lease terms, 90% of this rent is fixed and will contractually grow at 2% per year until 2022. The Company recorded a lease incentive asset which represents the consideration paid, less the existing deferred revenue balance of $94.0 million relating to the non-normal On April 1, 2019, MGM Northfield Park was added to the existing Master Lease and the annual rent payment increased by $60 million. Consistent with the Master Lease terms, 90% of this rent is fixed and will contractually grow at 2% per year until 2022. The annual rent payments under the Master Lease for the fourth lease year, which commenced on April 1, 2019, increased to $946.1 million from $770.3 million at the start of the third lease year. The increase was a result of the $50 million in additional rent for each of the Park MGM Transaction and Empire City in the beginning of 2019, the $60 million of additional rent for MGM Northfield Park on April 1, 2019, as well as the third 2.0% fixed annual rent escalator that went into effect on April 1, 2019. Straight-line rental revenues from the Master Lease, which includes the lease incentive asset amortization, were $219.8 million and $636.6 million for the three and nine months ended September 30, 2019, respectively, and were $186.6 million and $559.7 million for the three and nine months ended September 30, 2018, respectively. The Company also recognized revenue related to tenant reimbursements and other of $6.2 million and $18.6 million for the three and nine months ended September 30, 2019, respectively, and $30.1 million and $93.2 million for the three and nine months ended September 30, 2018, respectively. Under the Master Lease, future non-cancelable 10-year Year ending December 31, (in thousands) 2019 $ 236,515 2020 958,894 2021 976,262 2022 912,751 2023 890,126 Thereafter 1,922,713 $ 5,897,261 Lessee Leases. non-cancelable cost of $5.9 million and $17.9 million, respectively. Other information related to the Company’s operating leases was as follows (in thousands, except for lease term and discount rate information): Supplemental balance sheet information Balance at September 30, 2019 Operating lease right-of-use $ 280,020 Operating lease liabilities 336,452 Weighted-average remaining lease term (years) 59 Weighted-average discount rate (%) 7 % Maturities of operating lease liabilities were as follows: Year ending December 31, (in thousands) 2019 (excluding the nine months ended September 30, 2019) $ 4,541 2020 21,113 2021 24,996 2022 25,015 2023 24,875 Thereafter 1,357,650 Total future minimum lease payments 1,458,190 Less: Amount of lease payments representing interest (1,121,738 ) Total $ 336,452	LEASES Master Lease. five years triple-net In connection with the commencement of the third lease year on April 1, 2018, the base rent under the Master Lease increased to $695.8 million, resulting in total annual rent under the Master Lease of $770.3 million. Rent under the Master Lease consists of a “base rent” component and a “percentage rent” component. As of December 31, 2018, the base rent represents approximately 90% of the rent payments due under the Master Lease and the percentage rent represents approximately 10% of the rent payments due under the Master Lease. The base rent includes a fixed annual rent escalator of 2.0% for the second through the sixth lease years (as defined in the Master Lease). Thereafter, the annual escalator of 2.0% will be subject to the Tenant and, without duplication, the operating subsidiary sublessees of the Tenant (the “Operating Subtenants”), collectively meeting an adjusted net revenue to rent ratio of 6.25:1.00 based on their net revenue from the leased properties subject to the Master Lease (as determined in accordance with U.S. GAAP, adjusted to exclude net revenue attributable to certain scheduled subleases and, at the Tenant’s option, reimbursed cost revenue). The percentage rent will initially be a fixed amount for approximately the first six years and will then be adjusted every five years based on the average actual annual net revenues of the Tenant and, without duplication, the Operating Subtenants, from the leased properties subject to the Master Lease at such time for the trailing five calendar-year period (calculated by multiplying the average annual net revenues, excluding net revenue attributable to certain scheduled subleases and, at the Tenant’s option, reimbursed cost revenue, for the trailing five calendar-year period by 1.4%). In connection with the MGM National Harbor Transaction on October 5, 2017, the base rent under the Master Lease increased to $682.2 million and the percentage rent to $74.5 million, prorated for the remainder of the second lease year, resulting in total annual rent under the Master Lease of $756.7 million. As a result of this transaction, the Master Lease was amended to provide that the initial term with respect to MGM National Harbor ends on August 31, 2024. Thereafter, the initial term of the Master Lease with respect to MGM National Harbor may be renewed at the option of the Tenant for an initial renewal period lasting until the earlier of the end of the then-current term of the Master Lease or the next renewal term (depending on whether MGM elects to renew the other properties under the Master Lease in connection with the expiration of the initial 10 years term). If, however, the Tenant chooses not to renew the lease with respect to MGM National Harbor after the initial MGM National Harbor term under the Master Lease, the Tenant would also lose the right to renew the Master Lease with respect to the rest of the properties when the initial 10 In connection with the Borgata Transaction on August 1, 2016, rent under the Master Lease increased by $100 million from the initial rent of $550 million, $90 million of which relates to the base rent for the initial term and the remaining $10 million of which relates to the percentage rent. Following the closing of the Borgata Transaction, the base rent under the Master Lease became $585 million for the initial term and the percentage rent became $65 million, prorated for the remainder of the first lease year after the Borgata Transaction. Straight-line rental revenues from the Master Lease for the years ended December 31, 2018 and 2017 were $746.3 million and $675.1 million, respectively. The Company also recognized revenue related to tenant reimbursements and other of $123.2 million and $90.6 million for the years ended December 31, 2018 and 2017, respectively. Straight-line rental revenues from the Master Lease for the year ended December 31, 2016 were $419.2 million. Rental revenues from the Master Lease for the year ended December 31, 2016 represents activity from the IPO Date through December 31, 2016. The Company also recognized revenue related to tenant reimbursements and other of $48.3 million for the year ended December 31, 2016. Under the Master Lease, future non-cancelable 10-year Year ending December 31, (in thousands) 2019 $ 780,782 2020 794,907 2021 809,315 2022 757,060 2023 738,435 Thereafter 1,568,769 Total $ 5,449,268 Refer to Note 1 and Note 3 for transactions that have been entered into but not yet occurred as of December 31, 2018.

Debt

Debt	9 Months Ended	12 Months Ended
	Sep. 30, 2019	Dec. 31, 2018
Debt Disclosure [Abstract]
Debt	DEBT Debt consists of the following: September 30, December 31, 2019 2018 (in thousands) Senior secured credit facility: Senior secured term loan A facility $ 467,063 $ 470,000 Senior secured term loan B facility 1,785,250 1,799,125 Senior secured revolving credit facility — 550,000 $ 1,050 5.625 1,050,000 1,050,000 $ 500 4.50 500,000 500,000 $ 750 5.75 750,000 — $ 350 4.50 350,000 350,000 4,902,313 4,719,125 Less: Unamortized discount and debt issuance costs (54,905 ) (52,176 ) $ 4,847,408 $ 4,666,949 Operating Partnership credit agreement. no Refer to Note 7 for further discussion of the Company’s interest rate swap agreements. Bridge Facility. Operating Partnership senior notes. Fair value of long-term debt. Deferred financing costs. non-cash non-cash	DEBT Debt consists of the following: December 31, 2018 2017 (in thousands) Senior secured credit facility: Senior secured term loan A facility $ 470,000 $ 273,750 Senior secured term loan B facility 1,799,125 1,817,625 Senior secured revolving credit facility 550,000 — $ 1,050 5.625 1,050,000 1,050,000 $ 500 4.50 500,000 500,000 $ 350 4.50 350,000 350,000 4,719,125 3,991,375 Less: Unamortized discount and debt issuance costs (52,176 ) (56,747 ) $ 4,666,949 $ 3,934,628 Operating Partnership credit agreement. In June 2018, the Operating Partnership amended its credit agreement to provide for a $750 million increase of the revolving facility to $1.4 billion, a $200 million increase on the term loan A facility, and extension of the maturities of the revolving facility and the term loan A facility to June 2023. Additionally, the revolving and term loan A facilities were repriced to LIBOR plus 1.75% to 2.25% determined by reference to the total net leverage ratio pricing grid. In addition, amortization payments under the term loan A facility will start on the last business day of each calendar quarter beginning September 30, 2019, for an amount equal to 0.625 Prior to the amendment, the term loan A facility was subject to amortization in equal quarterly installments of 2.5% of the initial aggregate principal amount to be payable each year. The Operating Partnership permanently repaid $3.8 million of the term loan A facility for the year ended December 31, 2018. The term loan B facility is subject to equal quarterly installments of 1.0% of the initial aggregate principal amount each year. The Operating Partnership permanently repaid $18.5 million of the term loan B facility in the year ended December 31, 2018 in accordance with the scheduled amortization. As of December 31, 2018, $550.0 million was drawn on the revolving credit facility. At December 31, 2018, the interest rate on the term loan A facility was 4.52%, the interest rate on the term loan B facility was 4.52% and the interest rate on the revolver facility was 4.43%. See Note 7 for further discussion of the Operating Partnership’s interest rate swap agreements related to the term loan B facility. No letters of credit were outstanding under the Operating Partnership senior credit facility at December 31, 2018. The credit agreement contains customary representations and warranties, events of default and positive and negative covenants. The revolving credit facility and term loan A facility also require that the Operating Partnership maintain compliance with a maximum secured net debt to adjusted total asset ratio, a maximum total net debt to adjusted asset ratio and a minimum interest coverage ratio. The Operating Partnership was in compliance with its financial covenants at December 31, 2018. The revolving credit facility and the term loan facilities are both guaranteed by each of the Operating Partnership’s existing and subsequently acquired direct and indirect wholly owned material domestic restricted subsidiaries, and secured by a first priority lien security interest on substantially all of the Operating Partnership’s and such restricted subsidiaries’ material assets, including mortgages on its real estate, excluding the real estate assets of MGM National Harbor and Empire City, and subject to other customary exclusions. Operating Partnership senior notes. In August 2016, the Operating Partnership issued $500 million in aggregate principal amount of 4.50% senior notes due 2026. The senior notes will mature on September 1, 2026. Interest on the senior notes is payable on March 1 and September 1 of each year. In September 2017, the Operating Partnership issued $350 million in aggregate principal amount of 4.50% senior notes due 2028. The senior notes will mature on January 15, 2028. Interest on the senior notes is payable on January 15 and July 15 of each year. Subsequent to year end, in January 2019, the Operating Partnership issued $750 million in aggregate principal amount of 5.75% senior notes due 2027. The senior notes will mature on February 1, 2027. Interest on the senior notes is payable on February 1 and August 1 of each year, commencing on August 1, 2019. Each series of the Operating Partnership’s senior notes are fully and unconditionally guaranteed, jointly and severally, on a senior basis by all of the Operating Partnership’s subsidiaries that guarantee the Operating Partnership’s credit facilities, other than MGP Finance Co-Issuer, co-issuer Maturities of debt. Year ending December 31, (in thousands) 2019 $ 24,375 2020 30,250 2021 30,250 2022 30,250 2023 997,375 Thereafter 3,606,625 $ 4,719,125 Fair value of long-term debt. Deferred financing costs. non-cash

Derivatives and Hedging Activit

Derivatives and Hedging Activities	9 Months Ended	12 Months Ended
	Sep. 30, 2019	Dec. 31, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivatives and Hedging Activities	DERIVATIVES AND HEDGING ACTIVITIES The Company uses derivative instruments to mitigate the effects of interest rate volatility inherent in its variable rate debt, which could unfavorably impact our future earnings and forecasted cash flows. The Company does not use derivative instruments for speculative or trading purposes. The Operating Partnership is party to interest rate swaps, summarized in the table below, to mitigate the interest rate risk inherent in its senior credit facility. As of September 30, 2019, the Operating Partnership pays a weighted average fixed rate of 1.707% on a total notional amount of $1.5 billion. Notional Amount Weighted Average Fair Value Asset Effective Date Maturity Date (in thousands, except percentages) $300,000 1.158% $3,393 September 6, 2019 December 31, 2024 $1,200,000 1.844% $(9,926 ) May 3, 2017 November 30, 2021 400,000 2.252% (31,370 ) October 1, 2019 December 31, 2029 900,000 1.801% (13,274 ) November 30, 2021 December 31, 2024 $(54,570 ) In June 2019, the Operating Partnership entered into interest rate swap agreements, effective November 30, 2021, that will mature in December 2024 with a combined notional amount of $900 million. The weighted average fixed rate paid under the swap agreements is 1.801% and the variable rate received resets monthly to the one-month In September 2019, the Operating Partnership entered into an interest rate swap agreement, effective September 6, 2019, that will mature in December 2024 with a notional amount of $300 million. The fixed rate paid under the swap agreement is 1.158% and the variable rate received resets monthly to the one-month In September 2019, the Operating Partnership modified and extended certain of its existing interest rate swaps with a combined notional amount of $400 million, effective October 1, 2019. The weighted average fixed rate paid under the modified swap agreements is 2.252% and the variable rate received resets monthly to the one-month As of September 30, 2019, and December 31, 2018, all of the Company’s derivative financial instruments have been designated as cash flow hedges and qualify for hedge accounting. The Company expects to have variable rate debt outstanding for the duration and amount of its interest rate swap agreements. As of September 30, 2019, the fair values of the Company’s interest rate swaps were $3.4 million recorded as an asset within prepaid expenses and other assets, and $ 54.6 20.5 5.6	DERIVATIVES AND HEDGING ACTIVITIES The Company uses derivative instruments to mitigate the effects of interest rate volatility inherent in its variable rate debt, which could unfavorably impact our future earnings and forecasted cash flows. The Company does not use derivative instruments for speculative or trading purposes. The Operating Partnership is party to interest rate swaps to mitigate the interest rate risk inherent in its senior secured term loan B facility. As of December 31, 2018 and 2017, the Operating Partnership pays a weighted average fixed rate of 1.844%, on total notional amount of $1.2 billion, and the variable rate received will reset monthly to the one-month one-month For the years ended December 31, 2018 and 2017, the amount recorded in other comprehensive income related to the derivative instruments was a net gain of $4.1 million and a net gain of $9.8 million, respectively. For the years ended December 31, 2018 and 2017, the Operating Partnership recorded interest income of $1.1 million and interest expense of $9.2 million, respectively, related to the swap agreements.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2018
Income Tax Disclosure [Abstract]
INCOME TAXES	INCOME TAXES The Company elected to be treated as a REIT as defined under Section 856(a) of the Internal Revenue Code of 1986, as amended (the “Code”), commencing with its taxable year ended December 31, 2016. To qualify as a REIT, the Company must meet certain organizational, income, asset and distribution tests. Accordingly, except as described below, the Company will generally not be subject to corporate U.S. federal or state income tax to the extent that it makes qualifying distributions of all of its taxable income to its shareholders and provided it satisfies on a continuing basis, through actual investment and operating results, the REIT requirements, including certain asset, income, distribution and share ownership tests. U.S. federal income tax law generally requires that a REIT distribute annually at least 90% of its REIT taxable income, without regard to the deduction for dividends paid and excluding net capital gains, and that it pays taxes at regular corporate income tax rates to the extent that it annually distributes less than 100% of its taxable income. The Company distributed 100% of its taxable income in the taxable year ended December 31, 2018 and expects to do so in future years. Accordingly, the accompanying combined and consolidated financial statements do not reflect a provision for federal income taxes for its REIT operations; however, the Company is subject to federal, state and local income tax on its TRS operations and may still be subject to federal excise tax, as well as certain state and local income and franchise taxes on its REIT operations. The Company’s TRS owned the real estate assets and operations of Northfield that were acquired on July 6, 2018. The Company recorded a tax provision of $5.1 million in discontinued operations and a tax benefit of $1.2 million in continuing operations for a total tax provision of $3.9 million related to the operations of the TRS for the year ended December 31, 2018. On December 22, 2017, the U.S. government enacted comprehensive tax legislation commonly referred to as the Tax Cuts and Jobs Act (the “Tax Act”). The Tax Act made broad and complex changes to the U.S. tax code, including, but not limited to, reducing the U.S. federal corporate tax rate from 35 percent to 21 percent, creating a new limitation on deductible interest expense, and significantly changing the manner in which income from foreign operations are taxed in the U.S. Given that the Company is not subject to corporate U.S. federal income tax to the extent that it makes qualifying distributions of all of its taxable income to its shareholders, changes made by the Tax Act had no impact on the provision for federal income taxes for the year ended December 31, 2017. Consequently, the Company’s accounting for the Tax Act was complete as of December 31, 2017. The Landlord is required to join in the filing of a New Jersey consolidated corporation business tax return under the New Jersey Casino Control Act and include in such return its income and expenses associated with its New Jersey assets and is thus subject to an entity level tax in New Jersey. Although the consolidated New Jersey return also includes MGM and certain of its subsidiaries, the Company is required to record New Jersey state income taxes in the accompanying combined and consolidated financial statements as if the Landlord was taxed for state purposes on a stand-alone basis. The Company and MGM have entered into a tax sharing agreement providing for an allocation of taxes due in the consolidated New Jersey return. Pursuant to this agreement, the Landlord will only be responsible for New Jersey taxes on any gain that may be realized upon a future sale of the New Jersey assets resulting solely from an appreciation in value of such assets over their value on the date they were contributed to the Landlord by a subsidiary of MGM. MGM is responsible for all other taxes reported in the New Jersey consolidated return and, accordingly, the income tax balances related to such taxes are reflected within noncontrolling interest within the accompanying financial statements. No The provision for income taxes attributable to income (loss) before income taxes is as follows: Year Ended December 31, 2018 2017 2016 (in thousands) Federal: Current $ — $ — $ — Deferred (1,142 ) — — Provision for federal income taxes on continuing operations $ (1,142 ) $ — $ — State: Current $ 5,746 $ 1,729 $ 2,156 Deferred 1,175 3,177 108 Provision for state income taxes on continuing operations $ 6,921 $ 4,906 $ 2,264 A reconciliation of the federal income tax statutory rate and the Company’s effective tax rate on income from continuing operations is as follows: Year Ended December 31, 2018 2017 2016 Federal income tax statutory rate 21.0 % 35.0 % 35.0 % Federal valuation allowance — — — Income not subject to federal income tax (21.5 ) (35.0 ) (35.0 ) State taxes 3.1 2.9 6.0 Effective tax rate on income from continuing operations 2.6 % 2.9 % 6.0 % The major tax-effected December 31, 2018 2017 (in thousands) Deferred tax asset — federal and state Accruals, reserves and other $ 1,844 $ — Total deferred tax asset $ 1,844 $ — Deferred tax liability — federal and state Real estate investments, net $ (33,466 ) $ (28,544 ) Other intangible assets, net (2,012 ) — Total deferred tax liability (35,478 ) (28,544 ) Net deferred tax liability $ (33,634 ) $ (28,544 ) The Company assesses its tax positions using a two-step no No The Company files income tax returns in the U.S. federal jurisdiction and various state and local jurisdictions. All returns are subject to examination by the relevant taxing authorities as of December 31, 2018.

Shareholders' Equity and Partne

Shareholders' Equity and Partners' Capital	9 Months Ended	12 Months Ended
	Sep. 30, 2019	Dec. 31, 2018
Equity [Abstract]
SHAREHOLDERS' EQUITY AND PARTNERS' CAPITAL	SHAREHOLDERS’ EQUITY AND PARTNERS’ CAPITAL MGP shareholders. On April 30, 2019, the Company entered into an “at-the-market-offering” Operating Partnership capital. On January 31, 2019, in connection with the Company’s registered offering of Class A shares, the Operating Partnership issued 19.6 million Operating Partnership units to the Company and MGP’s indirect ownership percentage in the Operating Partnership increased from 25.4% to 30.3%. On March 7, 2019, in connection with the Park MGM Transaction, the Operating Partnership issued 1.0 million Operating Partnership units to a subsidiary of MGM and MGP’s indirect ownership percentage in the Operating Partnership decreased from 30.3% to 30.2%. On April 1, 2019, in connection with the Northfield OpCo Transaction, 9.4 million Operating Partnership units were redeemed by the Operating Partnership and MGP’s indirect ownership percentage in the Operating Partnership increased from 30.2% to 31.2%. During the three and nine months ended September 30, 2019, in connection with the Company’s issuance of Class A shares under the ATM program, the Operating Partnership issued 2.8 million and 4.9 million Operating Partnership units to the Company, respectively. MGP’s indirect ownership percentage in the Operating Partnership as of September 30, 2019 was 32.3%. Accumulated Other Comprehensive Income (Loss). non-shareholder Cash Flow Other Total (in thousands) Balance at January 1, 2019 $ 4,208 $ — $ 4,208 Other comprehensive loss before reclassifications (13,765 ) — (13,765 ) Amounts reclassified from accumulated other comprehensive income to interest expense (1,847 ) — (1,847 ) Empire City Transaction — (195 ) (195 ) Class A share issuances — 774 774 Park MGM Transaction — (16 ) (16 ) Other comprehensive income (loss) (15,612 ) 563 (15,049 ) Less: Other comprehensive loss attributable to noncontrolling interest 10,895 — 10,895 Balance at March 31, 2019 (509 ) 563 54 Other comprehensive loss before reclassifications (29,008 ) — (29,008 ) Amounts reclassified from accumulated other comprehensive income to interest expense (1,767 ) — (1,767 ) Class A share issuances — (105 ) (105 ) Northfield OpCo Transaction — 2 2 Other comprehensive loss (30,775 ) (103 ) (30,878 ) Less: Other comprehensive loss attributable to noncontrolling interest 21,128 — 21,128 Balance at June 30, 2019 (10,156 ) 460 (9,696 ) Other comprehensive loss before reclassifications (17,989 ) — (17,989 ) Amounts reclassified from accumulated other comprehensive loss to interest expense (1,281 ) — (1,281 ) Class A share issuances — (200 ) (200 ) Other comprehensive loss (19,270 ) (200 ) (19,470 ) Less: Other comprehensive loss attributable to noncontrolling interest 13,037 — 13,037 Balance at September 30, 2019 $ (16,389 ) $ 260 $ (16,129 ) MGP dividends and Operating Partnership distributions. non-dividend	SHAREHOLDERS’ EQUITY AND PARTNERS’ CAPITAL MGP shareholders Subsequent to year end, on January 31, 2019, the Company completed an offering of 19.6 million Class A shares representing limited liability company interests in a registered public offering, including 2.6 million Class A shares sold pursuant to the exercise in full by the underwriters of their over-allotment option, for net proceeds of approximately $548.4 million after deducting underwriting discounts and commissions. Operating Partnership capital. On October 5, 2017, in connection with the MGM National Harbor Transaction, the Operating Partnership issued 9.8 million Operating Partnership units to a subsidiary of MGM. Subsequent to year end, on January 29, 2019, in connection with the Empire City Transaction, the Operating Partnership issued 12.9 million Operating Partnership units to a subsidiary of MGM. Subsequent to year end, on January 31, 2019, in connection with the Company’s registered offering of Class A shares, the Operating Partnership issued 19.6 million Operating Partnership units to the Company. Accumulated Other Comprehensive Income. non-shareholder Cash Flow Hedges (in thousands) Balance at January 1, 2017 $ 445 Other comprehensive income before reclassifications 566 Amounts reclassified from accumulated other comprehensive income to interest expense 9,216 Other comprehensive income 9,782 Less: Other comprehensive (income) attributable to noncontrolling interest (7,119 ) Balance at December 31, 2017 3,108 Other comprehensive income before reclassifications 5,258 Amounts reclassified from accumulated other comprehensive income to interest expense (1,130 ) Other comprehensive income 4,128 Less: Other comprehensive (income) attributable to noncontrolling interest (3,028 ) Balance at December 31, 2018 $ 4,208 MGP dividends and Operating Partnership distributions. The non-dividend and $0.4406 non-dividend and $0.3755 non-dividend

Net Income Per Class A Share

Net Income Per Class A Share	9 Months Ended	12 Months Ended
	Sep. 30, 2019	Dec. 31, 2018
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
NET INCOME PER CLASS A SHARE	NET INCOME PER CLASS A SHARE The table below provides net income and the number of Class A shares used in the computations of “basic” net income per share, which utilizes the weighted-average number of Class A shares outstanding without regard to dilutive potential Class A shares, and “diluted” net income per share, which includes all such shares. Net income per share has not been presented for the Class B shareholder as the Class B share is not entitled to any economic rights in the Company. Three Months Ended Nine Months Ended 2019 2018 2019 2018 (in thousands, except share amounts) Numerator: Income from continuing operations $ 68,553 $ 55,974 $ 186,470 $ 162,202 Income from continuing operations attributable to noncontrolling interest (46,038 ) (40,208 ) (126,924 ) (117,460 ) Income from continuing operations attributable to Class A shares—basic and diluted 22,515 15,766 59,546 44,742 Income from discontinued operations — 13,949 16,216 13,949 Income from discontinued operations attributable to noncontrolling interest — (10,231 ) (11,434 ) (10,231 ) Income from discontinued operations attributable to Class A shares—basic and diluted — 3,718 4,782 3,718 Net income attributable to Class A shares—basic and diluted $ 22,515 $ 19,484 $ 64,328 $ 48,460 Denominator: Weighted average Class A shares outstanding (1) 93,165,443 71,005,052 89,440,552 70,991,129 Effect of dilutive (2)(3) 157,497 196,739 204,557 183,141 Weighted average Class A shares outstanding (1) 93,322,940 71,201,791 89,645,109 71,174,270 (1) Includes weighted average deferred share units granted to certain members of the board of directors. (2) No shares related to outstanding share-based compensation awards were excluded due to being antidilutive. (3) Diluted net income per Class A share does not assume conversion of the Operating Partnership units held by MGM as such conversion would be antidilutive.	NET INCOME PER CLASS A SHARE The table below provides net income and the number of Class A shares used in the computations of “basic” net income per share, which utilizes the weighted-average number of Class A shares outstanding without regard to dilutive potential Class A shares, and “diluted” net income per share, which includes all such shares. Net income attributable to Class A shares, weighted average Class A shares outstanding and the effect of dilutive securities outstanding are presented for the period subsequent to the IPO Date. Net income per share has not been presented for the Class B shareholder as the Class B share is not entitled to any economic rights in the Company. Years ended April 25 — 2018 2017 2016 (in thousands, except share amounts) Numerator: Income from continuing operations, net of tax $ 214,139 $ 165,990 $ 35,346 Income from continuing operations attributable to noncontrolling interest (155,220 ) (124,215 ) (5,408 ) Income from continuing operations attributable to Class A shares — basic and diluted 58,919 41,775 29,938 Income from discontinued operations, net of tax 30,563 — — Income from discontinued operations attributable to noncontrolling interest (22,417 ) — — Income from discontinued operations attributable to Class A shares — basic and diluted 8,146 — — Net income attributable to Class A shares — basic and diluted $ 67,065 $ 41,775 $ 29,938 Denominator: Weighted average Class A shares outstanding (1) 70,997,589 61,733,136 57,502,158 Effect of dilutive shares for diluted net income per Class A share (2) 188,085 183,410 249,331 Weighted average Class A shares outstanding (1) 71,185,674 61,916,546 57,751,489 (1) Includes weighted average deferred share units granted to certain members of the board of directors. (2) No shares related to outstanding share-based compensation awards were excluded due to being antidilutive. (3) Diluted net income per Class A share does not assume conversion of the Operating Partnership units held by MGM as such conversion would be antidilutive.

Net Income Per Operating Partne

Net Income Per Operating Partnership Unit	9 Months Ended	12 Months Ended
	Sep. 30, 2019	Dec. 31, 2018
Condensed Income Statements, Captions [Line Items]
NET INCOME PER OPERATING PARTNERSHIP UNIT	NET INCOME PER CLASS A SHARE The table below provides net income and the number of Class A shares used in the computations of “basic” net income per share, which utilizes the weighted-average number of Class A shares outstanding without regard to dilutive potential Class A shares, and “diluted” net income per share, which includes all such shares. Net income per share has not been presented for the Class B shareholder as the Class B share is not entitled to any economic rights in the Company. Three Months Ended Nine Months Ended 2019 2018 2019 2018 (in thousands, except share amounts) Numerator: Income from continuing operations $ 68,553 $ 55,974 $ 186,470 $ 162,202 Income from continuing operations attributable to noncontrolling interest (46,038 ) (40,208 ) (126,924 ) (117,460 ) Income from continuing operations attributable to Class A shares—basic and diluted 22,515 15,766 59,546 44,742 Income from discontinued operations — 13,949 16,216 13,949 Income from discontinued operations attributable to noncontrolling interest — (10,231 ) (11,434 ) (10,231 ) Income from discontinued operations attributable to Class A shares—basic and diluted — 3,718 4,782 3,718 Net income attributable to Class A shares—basic and diluted $ 22,515 $ 19,484 $ 64,328 $ 48,460 Denominator: Weighted average Class A shares outstanding (1) 93,165,443 71,005,052 89,440,552 70,991,129 Effect of dilutive (2)(3) 157,497 196,739 204,557 183,141 Weighted average Class A shares outstanding (1) 93,322,940 71,201,791 89,645,109 71,174,270 (1) Includes weighted average deferred share units granted to certain members of the board of directors. (2) No shares related to outstanding share-based compensation awards were excluded due to being antidilutive. (3) Diluted net income per Class A share does not assume conversion of the Operating Partnership units held by MGM as such conversion would be antidilutive.	NET INCOME PER CLASS A SHARE The table below provides net income and the number of Class A shares used in the computations of “basic” net income per share, which utilizes the weighted-average number of Class A shares outstanding without regard to dilutive potential Class A shares, and “diluted” net income per share, which includes all such shares. Net income attributable to Class A shares, weighted average Class A shares outstanding and the effect of dilutive securities outstanding are presented for the period subsequent to the IPO Date. Net income per share has not been presented for the Class B shareholder as the Class B share is not entitled to any economic rights in the Company. Years ended April 25 — 2018 2017 2016 (in thousands, except share amounts) Numerator: Income from continuing operations, net of tax $ 214,139 $ 165,990 $ 35,346 Income from continuing operations attributable to noncontrolling interest (155,220 ) (124,215 ) (5,408 ) Income from continuing operations attributable to Class A shares — basic and diluted 58,919 41,775 29,938 Income from discontinued operations, net of tax 30,563 — — Income from discontinued operations attributable to noncontrolling interest (22,417 ) — — Income from discontinued operations attributable to Class A shares — basic and diluted 8,146 — — Net income attributable to Class A shares — basic and diluted $ 67,065 $ 41,775 $ 29,938 Denominator: Weighted average Class A shares outstanding (1) 70,997,589 61,733,136 57,502,158 Effect of dilutive shares for diluted net income per Class A share (2) 188,085 183,410 249,331 Weighted average Class A shares outstanding (1) 71,185,674 61,916,546 57,751,489 (1) Includes weighted average deferred share units granted to certain members of the board of directors. (2) No shares related to outstanding share-based compensation awards were excluded due to being antidilutive. (3) Diluted net income per Class A share does not assume conversion of the Operating Partnership units held by MGM as such conversion would be antidilutive.
MGP Operating Partnership
Condensed Income Statements, Captions [Line Items]
NET INCOME PER OPERATING PARTNERSHIP UNIT	NET INCOME PER OPERATING PARTNERSHIP UNIT The table below provides net income and the number of Operating Partnership units used in the computations of “basic” net income per Operating Partnership unit, which utilizes the weighted-average number of Operating Partnership units outstanding without regard to dilutive potential Operating Partnership units, and “diluted” net income per Operating Partnership units, which includes all such Operating Partnership units. Three Months Ended September 30, Nine Months Ended September 30, 2019 2018 2019 2018 (in thousands, except share amounts) Numerator: Income from continuing operations $ 68,553 $ 55,974 $ 186,470 $ 162,202 Income from discontinued operations — 13,949 16,216 13,949 Net income—basic and diluted $ 68,553 $ 69,923 $ 202,686 $ 176,151 Denominator: Weighted average Operating Partnership units outstanding (1) 292,867,986 266,139,175 290,661,305 266,125,252 Effect of dilutive shares for diluted net income per Operating Partnership unit (2) 157,497 196,739 204,557 183,141 Weighted average Operating Partnership units outstanding (1) 293,025,483 266,335,914 290,865,862 266,308,393 (1) Includes weighted average deferred share units granted to certain members of the Board of Directors. (2) No shares related to outstanding share-based compensation awards were excluded due to being antidilutive.	NET INCOME PER OPERATING PARTNERSHIP UNIT The table below provides net income and the number of Operating Partnership units used in the computations of “basic” net income per Operating Partnership unit, which utilizes the weighted-average number of Operating Partnership units outstanding without regard to dilutive potential Operating Partnership units, and “diluted” net income per Operating Partnership units, which includes all such Operating Partnership units. Net income attributable to Operating Partnership units, weighted average Operating Partnership units outstanding and the effect of dilutive securities outstanding are presented for the period subsequent to the IPO Date. Years ended April 25 — 2018 2017 2016 (in thousands, except share amounts) Numerator: Income from continuing operations, net of tax $ 214,139 $ 165,990 $ 119,729 Income from discontinued operations, net of tax 30,563 — — Net income — basic and diluted $ 244,702 $ 165,990 $ 119,729 Denominator: Weighted average Operating Partnership units outstanding (1) 266,131,712 249,451,258 232,181,070 Effect of dilutive shares for diluted net income per Operating Partnership unit (2) 188,085 183,410 249,331 Weighted average Operating Partnership units outstanding (1) 266,319,797 249,634,668 232,430,401 (1) Includes weighted average deferred share units granted to certain members of the Board of Directors. (2) No shares related to outstanding share-based compensation awards were excluded due to being antidilutive.

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended	12 Months Ended
	Sep. 30, 2019	Dec. 31, 2018
Commitments and Contingencies Disclosure [Abstract]
COMMITMENTS AND CONTINGENCIES	COMMITMENTS AND CONTINGENCIES Litigation.	COMMITMENTS AND CONTINGENCIES Leases. non-cancelable non-cancelable Year ending December 31, (in thousands) 2019 $ 19,868 2020 21,113 2021 24,996 2022 25,015 2023 24,875 Thereafter 1,310,253 $ 1,426,120 Litigation.

Condensed Consolidating Financi

Condensed Consolidating Financial Information	9 Months Ended	12 Months Ended
	Sep. 30, 2019	Dec. 31, 2018
Condensed Financial Information Disclosure [Abstract]
CONDENSED CONSOLIDATING FINANCIAL INFORMATION	CONDENSED CONSOLIDATING FINANCIAL INFORMATION The Operating Partnership’s senior notes were co-issued Co-Issuer, Co-Issuer, The guarantee of a subsidiary guarantor will be automatically released upon (i) a sale or other disposition (including by way of consolidation or merger) of the subsidiary guarantor, or the capital stock of the subsidiary guarantor; (ii) the sale or disposition of all or substantially all of the assets of the subsidiary guarantor; (iii) the designation in accordance with the indenture of a subsidiary guarantor as an unrestricted subsidiary; (iv) at such time as such subsidiary guarantor is no longer a subsidiary guarantor or other obligor with respect to any credit facilities or capital markets indebtedness of the Operating Partnership; or (v) defeasance or discharge of the notes. CONSOLIDATING BALANCE SHEET INFORMATION September 30, 2019 Operating Co-Issuer Guarantor Eliminations Consolidated (in thousands) Real estate investments, net $ 507 $ — $ 10,893,614 $ — $ 10,894,121 Lease incentive asset — — 532,186 — 532,186 Cash and cash equivalents 153,526 — — — 153,526 Tenant and other receivables, net 463 — — — 463 Intercompany 1,169,999 — — (1,169,999 ) — Prepaid expenses and other assets 15,730 — 11,683 — 27,413 Investments in subsidiaries 10,126,379 — — (10,126,379 ) — Above market lease, asset — — 41,834 — 41,834 Operating lease right-of-use 477 — 279,543 — 280,020 Total assets $ 11,467,081 $ — $ 11,758,860 $ (11,296,378 ) $ 11,929,563 Debt, net 4,847,408 — — — 4,847,408 Due to MGM Resorts International and affiliates 298 — — — 298 Intercompany — — 1,169,999 (1,169,999 ) — Accounts payable, accrued expenses and other liabilities 58,457 — 1,480 — 59,937 Accrued interest 37,407 — — — 37,407 Dividend and distribution payable 138,730 — — — 138,730 Deferred revenue — — 95,306 — 95,306 Deferred income taxes, net — — 29,721 — 29,721 Operating lease liabilities 477 — 335,975 — 336,452 Total liabilities 5,082,777 — 1,632,481 (1,169,999 ) 5,545,259 General partner — — — — — Limited partners 6,384,304 — 10,126,379 (10,126,379 ) 6,384,304 Total partners’ capital 6,384,304 — 10,126,379 (10,126,379 ) 6,384,304 Total liabilities and partners’ capital $ 11,467,081 $ — $ 11,758,860 $ (11,296,378 ) $ 11,929,563 CONSOLIDATING BALANCE SHEET INFORMATION December 31, 2018 Operating Co-Issuer Guarantor Eliminations Consolidated (in thousands) Real estate investments, net $ 572 $ — $ 10,505,557 $ — $ 10,506,129 Cash and cash equivalents 3,995 — — — 3,995 Tenant and other receivables, net 26 — 7,642 — 7,668 Intercompany 841,179 — — (841,179 ) — Prepaid expenses and other assets 34,813 — — — 34,813 Investments in subsidiaries 9,790,350 — — (9,790,350 ) — Above market lease, asset — — 43,014 — 43,014 Assets held for sale — — 355,688 — 355,688 Total assets $ 10,670,935 $ — $ 10,911,901 $ (10,631,529 ) $ 10,951,307 Debt, net 4,666,949 — — — 4,666,949 Due to MGM Resorts International and affiliates 227 — — — 227 Intercompany — — 841,179 (841,179 ) — Accounts payable, accrued expenses and other liabilities 13,102 — 7,694 — 20,796 Above market lease, liability — — 46,181 — 46,181 Accrued interest 26,096 — — — 26,096 Dividend and distribution payable 119,055 — — — 119,055 Deferred revenue — — 163,926 — 163,926 Deferred income taxes, net — — 33,634 — 33,634 Liabilities related to assets held for sale — — 28,937 — 28,937 Total liabilities 4,825,429 — 1,121,551 (841,179 ) 5,105,801 General partner — — — — — Limited partners 5,845,506 — 9,790,350 (9,790,350 ) 5,845,506 Total partners’ capital 5,845,506 — 9,790,350 (9,790,350 ) 5,845,506 Total liabilities and partners’ capital $ 10,670,935 $ — $ 10,911,901 $ (10,631,529 ) $ 10,951,307 CONSOLIDATING STATEMENT OF OPERATIONS AND COMPREHENSIVE INCOME INFORMATION Three Months Ended September 30, 2019 Operating Co-Issuer Guarantor Eliminations Consolidated (in thousands) Revenues Rental revenue $ — $ — $ 219,847 $ — $ 219,847 Tenant reimbursements and other — — 6,164 — 6,164 Total revenues — — 226,011 — 226,011 Expenses Depreciation 22 — 71,935 — 71,957 Property transactions, net — — 9,921 — 9,921 Ground lease and other reimbursable expenses — — 5,920 — 5,920 Acquisition-related expenses 92 — — — 92 General and administrative 4,476 — — — 4,476 Total expenses 4,590 — 87,776 — 92,366 Equity in earnings of subsidiaries 136,256 — — (136,256 ) — Other income (expense) Interest income 241 — — — 241 Interest expense (63,048 ) — — — (63,048 ) Other (306 ) — — — (306 ) (63,113 ) — — — (63,113 ) Income before income taxes 68,553 — 138,235 (136,256 ) 70,532 Provision for income taxes — — (1,979 ) — (1,979 ) Net income $ 68,553 $ — $ 136,256 $ (136,256 ) $ 68,553 Other comprehensive income Net income $ 68,553 $ — $ 136,256 $ (136,256 ) $ 68,553 Unrealized loss on cash flow hedges, net (19,270 ) — — — (19,270 ) Comprehensive income $ 49,283 $ — $ 136,256 $ (136,256 ) $ 49,283 CONSOLIDATING STATEMENT OF OPERATIONS AND COMPREHENSIVE INCOME INFORMATION Three Months Ended September 30, 2018 Operating Co-Issuer Guarantor Eliminations Consolidated (in thousands) Revenues Rental revenue $ — $ — $ 186,564 $ — $ 186,564 Tenant reimbursements and other — — 30,095 — 30,095 Total revenues — — 216,659 — 216,659 Expenses Depreciation 45 — 63,423 — 63,468 Property transactions, net — — 339 — 339 Ground lease and other reimbursable expenses — — 29,168 — 29,168 Amortization of above market lease, net — — 171 — 171 Acquisition-related expenses 1,931 — — — 1,931 General and administrative 3,358 — — — 3,358 Total expenses 5,334 — 93,101 — 98,435 Equity in earnings of subsidiaries 129,568 — — (129,568 ) — Other income (expense) Interest income 5,452 — — (5,289 ) 163 Interest expense (58,743 ) — (5,289 ) 5,289 (58,743 ) Other (1,020 ) — — — (1,020 ) (54,311 ) — (5,289 ) — (59,600 ) Income from continuing operations before income taxes 69,923 — 118,269 (129,568 ) 58,624 Provision for income taxes — — (2,650 ) — (2,650 ) Income from continuing operations, net of tax 69,923 — 115,619 (129,568 ) 55,974 Income from discontinued operations, net of tax — — 13,949 — 13,949 Net income $ 69,923 $ — $ 129,568 $ (129,568 ) $ 69,923 Other comprehensive income Net income $ 69,923 $ — $ 129,568 $ (129,568 ) $ 69,923 Unrealized gain on cash flow hedges, net 4,736 — — — 4,736 Comprehensive income $ 74,659 $ — $ 129,568 $ (129,568 ) $ 74,659 CONSOLIDATING STATEMENT OF OPERATIONS AND COMPREHENSIVE INCOME INFORMATION Nine Months Ended September 30, 2019 Operating Co-Issuer Guarantor Eliminations Consolidated (in thousands) Revenues Rental revenue $ — $ — $ 636,575 $ — $ 636,575 Tenant reimbursements and other — — 18,618 — 18,618 Total revenues — — 655,193 — 655,193 Expenses Depreciation 65 — 222,997 — 223,062 Property transactions, net — — 11,344 — 11,344 Ground lease and other reimbursable expenses — — 17,760 — 17,760 Acquisition-related expenses 8,891 — — — 8,891 General and administrative 12,305 — — — 12,305 Total expenses 21,261 — 252,101 — 273,362 Equity in earnings of subsidiaries 409,665 — — (409,665 ) — Other income (expense) Interest income 7,806 — — (5,617 ) 2,189 Interest expense (190,973 ) — (5,617 ) 5,617 (190,973 ) Other (806 ) — — — (806 ) (183,973 ) — (5,617 ) — (189,590 ) Income from continuing operations before income taxes 204,431 — 397,475 (409,665 ) 192,241 Provision for income taxes (1,745 ) — (4,026 ) — (5,771 ) Income from continuing operations, net of tax 202,686 — 393,449 (409,665 ) 186,470 Income from discontinued operations, net of tax — — 16,216 — 16,216 Net income $ 202,686 $ — $ 409,665 $ (409,665 ) $ 202,686 Other comprehensive income Net income $ 202,686 $ — $ 409,665 $ (409,665 ) $ 202,686 Unrealized loss on cash flow hedges, net (65,657 ) — — — (65,657 ) Comprehensive income $ 137,029 $ — $ 409,665 $ (409,665 ) $ 137,029 CONSOLIDATING STATEMENT OF OPERATIONS AND COMPREHENSIVE INCOME INFORMATION Nine Months Ended September 30, 2018 Operating Co-Issuer Guarantor Eliminations Consolidated (in thousands) Revenues Rental revenue $ — $ — $ 559,690 $ — $ 559,690 Tenant reimbursements and other — — 93,198 — 93,198 Total revenues — — 652,888 — 652,888 Expenses Depreciation 87 — 199,846 — 199,933 Property transactions, net — — 18,851 — 18,851 Ground lease and other reimbursable expenses — — 90,435 — 90,435 Amortization of above market lease, net — — 514 — 514 Acquisition-related expenses 4,603 — — — 4,603 General and administrative 10,021 — — — 10,021 Total expenses 14,711 — 309,646 — 324,357 Equity in earnings of subsidiaries 346,758 — — (346,758 ) — Other income (expense) Interest income 7,762 — — (5,289 ) 2,473 Interest expense (157,249 ) — (5,289 ) 5,289 (157,249 ) Other (6,409 ) — — — (6,409 ) (155,896 ) — (5,289 ) — (161,185 ) Income from continuing operations before income taxes 176,151 — 337,953 (346,758 ) 167,346 Provision for income taxes — — (5,144 ) — (5,144 ) Income from continuing operations, net of tax 176,151 — 332,809 (346,758 ) 162,202 Income from discontinued operations, net of tax — — 13,949 — 13,949 Net income $ 176,151 $ — $ 346,758 $ (346,758 ) $ 176,151 Other comprehensive income Net income $ 176,151 $ — $ 346,758 $ (346,758 ) $ 176,151 Unrealized gain on cash flow hedges, net 27,372 — — — 27,372 Comprehensive income $ 203,523 $ — $ 346,758 $ (346,758 ) $ 203,523 CONSOLIDATING STATEMENT OF CASH FLOWS INFORMATION Nine Months Ended September 30, 2019 Operating Co-Issuer Guarantor Eliminations Consolidated (in thousands) Cash flows from operating activities Net cash provided by (used in) operating activities $ (762,230 ) $ — $ 677,713 $ — $ (84,517 ) Cash flows from investing activities Proceeds from Northfield OpCo Transaction 3,779 — — — 3,779 Net cash provided by investing activities 3,779 — — — 3,779 Cash flows from financing activities Net repayments under bank credit facility (566,813 ) — — — (566,813 ) Proceeds from issuance of debt 750,000 — — — 750,000 Deferred financing costs (9,983 ) — — — (9,983 ) Repayment of assumed bridge facility (245,950 ) — — — (245,950 ) Issuance of Operating Partnership units 699,362 — — — 699,362 Distributions paid (395,005 ) — — — (395,005 ) Cash received by Parent on behalf of Guarantor Subsidiaries, net 677,713 — (677,713 ) — — Other (1,342 ) — — — (1,342 ) Net cash provided by (used in) financing activities 907,982 — (677,713 ) — 230,269 Cash flows from discontinued operations, net Cash flows provided by operating activities, net — — 15,591 — 15,591 Cash flows used in investing activities, net — — (12 ) — (12 ) Cash flows used in financing activities, net — — (37,900 ) — (37,900 ) Net cash used in discontinued operations — — (22,321 ) — (22,321 ) Change in cash and cash equivalents classified as assets held for sale — — (22,321 ) — (22,321 ) Cash and cash equivalents Net increase for the period 149,531 — — — 149,531 Balance, beginning of period 3,995 — — — 3,995 Balance, end of period $ 153,526 $ — $ — $ — $ 153,526 CONSOLIDATING STATEMENT OF CASH FLOWS INFORMATION Nine Months Ended September 30, 2018 Operating Co-Issuer Guarantor Eliminations Consolidated (in thousands) Cash flows from operating activities Net cash provided by (used in) operating activities $ (149,511 ) $ — $ 574,348 $ — $ 424,837 Cash flows from investing activities Capital expenditures for property and equipment (191 ) — — — (191 ) Acquisition of Northfield (1,068,337 ) — — (1,068,337 ) Net cash used in investing activities (1,068,528 ) — — — (1,068,528 ) Cash flows from financing activities Net borrowings under bank credit facility 747,375 — — — 747,375 Deferred financing costs (17,490 ) — — — (17,490 ) Distributions paid (337,865 ) — — — (337,865 ) Cash received by Parent on behalf of Guarantor Subsidiaries 574,348 — (574,348 ) — — Net cash provided by (used in) financing activities 966,368 — (574,348 ) — 392,020 Cash flows from discontinued operations, net Cash flows provided by operating activities, net — — 8,250 — 8,250 Cash flows provided by investing activities, net — — 33,199 — 33,199 Cash flows used in financing activities, net — — — — — Net cash provided by discontinued operations — — 41,449 — 41,449 Cash flows from discontinued operations, net Change in cash and cash equivalents classified as assets held for sale — — 41,449 — 41,449 Cash and cash equivalents Net decrease for the period (251,671 ) — — — (251,671 ) Balance, beginning of period 259,722 — — — 259,722 Balance, end of period $ 8,051 $ — $ — $ — $ 8,051	CONSOLIDATING FINANCIAL INFORMATION The Operating Partnership’s senior notes were co-issued Co-Issuer, Co-Issuer, The guarantee of a subsidiary guarantor will be automatically released upon (i) a sale or other disposition (including by way of consolidation or merger) of the subsidiary guarantor, or the capital stock of the subsidiary guarantor; (ii) the sale or disposition of all or substantially all of the assets of the subsidiary guarantor; (iii) the designation in accordance with the indenture of a subsidiary guarantor as an unrestricted subsidiary; (iv) at such time as such subsidiary guarantor is no longer a subsidiary guarantor or other obligor with respect to any credit facilities or capital markets indebtedness of the Operating Partnership; or (v) defeasance or discharge of the notes. CONSOLIDATING BALANCE SHEET INFORMATION December 31, 2018 Operating Guarantor Partnership Co-Issuer Subsidiaries Eliminations Consolidated (in thousands) Real estate investments, net $ 572 $ — $ 10,505,557 $ — $ 10,506,129 Cash and cash equivalents 3,995 — — — 3,995 Tenant and other receivables, net 26 — 7,642 — 7,668 Intercompany 841,179 — — (841,179 ) — Prepaid expenses and other assets 34,813 — — — 34,813 Investments in subsidiaries 9,790,350 — — (9,790,350 ) — Above market lease, asset — — 43,014 — 43,014 Assets held for sale — — 355,688 — 355,688 Total assets $ 10,670,935 $ — $ 10,911,901 $ (10,631,529 ) $ 10,951,307 Debt, net 4,666,949 — — — 4,666,949 Due to MGM Resorts International and affiliates 227 — — — 227 Intercompany — — 841,179 (841,179 ) — Accounts payable, accrued expenses, and other liabilities 13,102 — 7,694 — 20,796 Above market lease, liability — — 46,181 — 46,181 Accrued interest 26,096 — — — 26,096 Distribution payable 119,055 — — — 119,055 Deferred revenue — — 163,926 — 163,926 Deferred income taxes, net — — 33,634 — 33,634 Liabilities related to assets held for sale — — 28,937 — 28,937 Total liabilities 4,825,429 — 1,121,551 (841,179 ) 5,105,801 General partner — — — — — Limited partners 5,845,506 — 9,790,350 (9,790,350 ) 5,845,506 Total partners’ capital 5,845,506 — 9,790,350 (9,790,350 ) 5,845,506 Total liabilities and partners’ capital $ 10,670,935 $ — $ 10,911,901 $ (10,631,529 ) $ 10,951,307 CONSOLIDATING BALANCE SHEET INFORMATION December 31, 2017 Operating Co-Issuer Guarantor Eliminations Consolidated (in thousands) Real estate investments, net $ 488 $ — $ 10,021,450 $ — $ 10,021,938 Cash and cash equivalents 259,722 — — — 259,722 Tenant and other receivables, net 299 — 6,086 — 6,385 Intercompany 1,383,397 — — (1,383,397 ) — Prepaid expenses and other assets 18,487 — — — 18,487 Investments in subsidiaries 8,479,388 — — (8,479,388 ) — Above market lease, asset — — 44,588 — 44,588 Total assets $ 10,141,781 $ — $ 10,072,124 $ (9,862,785 ) $ 10,351,120 Debt, net 3,934,628 — — — 3,934,628 Due to MGM Resorts International and affiliates 962 — — — 962 Intercompany — — 1,383,397 (1,383,397 ) — Accounts payable, accrued expenses, and other liabilities 4,154 — 6,086 — 10,240 Above market lease, liability — — 47,069 — 47,069 Accrued interest 22,565 — — — 22,565 Distribution payable 111,733 — — — 111,733 Deferred revenue — — 127,640 — 127,640 Deferred income taxes, net — — 28,544 — 28,544 Total liabilities 4,074,042 — 1,592,736 (1,383,397 ) 4,283,381 General partner — — — — — Limited partners 6,067,739 — 8,479,388 (8,479,388 ) 6,067,739 Total partners’ capital 6,067,739 — 8,479,388 (8,479,388 ) 6,067,739 Total liabilities and partners’ capital $ 10,141,781 $ — $ 10,072,124 $ (9,862,785 ) $ 10,351,120 CONSOLIDATING STATEMENT OF OPERATIONS AND COMPREHENSIVE INCOME INFORMATION Year Ended December 31, 2018 Operating Co-Issuer Guarantor Eliminations Consolidated (in thousands) Revenues Rental revenue $ — $ — $ 746,253 $ — $ 746,253 Tenant reimbursements and other — — 123,242 — 123,242 — — 869,495 — 869,495 Expenses Depreciation 108 — 266,514 — 266,622 Property transactions, net — — 20,319 — 20,319 Reimbursable expenses — — 119,531 — 119,531 Amortization of above market lease, net — — 686 — 686 Acquisition-related expenses 6,149 — — — 6,149 General and administrative 16,048 — — — 16,048 22,305 — 407,050 — 429,355 (22,305 ) — 462,445 — 440,140 Equity in earnings of subsidiaries 476,353 — — (476,353 ) — Other income (expense) Interest income 13,377 — — (10,876 ) 2,501 Interest expense (215,532 ) — (10,876 ) 10,876 (215,532 ) Other (7,191 ) — — — (7,191 ) (209,346 ) — (10,876 ) — (220,222 ) Income (loss) from continuing operations before income taxes 244,702 — 451,569 (476,353 ) 219,918 Provision for income taxes — — (5,779 ) — (5,779 ) Income from continuing operations, net of tax $ 244,702 $ — $ 445,790 $ (476,353 ) $ 214,139 Income from discontinued operations, net of tax (Note 3) — — 30,563 — 30,563 Net income (loss) $ 244,702 $ — $ 476,353 $ (476,353 ) $ 244,702 Other comprehensive income (loss) Net income (loss) 244,702 — 476,353 (476,353 ) 244,702 Unrealized gain on cash flow hedges 4,128 — — — 4,128 Comprehensive income (loss) $ 248,830 $ — $ 476,353 $ (476,353 ) $ 248,830 CONSOLIDATING STATEMENT OF CASH FLOWS INFORMATION Year Ended December 31, 2018 Operating Co-Issuer Guarantor Eliminations Consolidated (in thousands) Cash flows from operating activities Net cash provided by (used in) operating activities $ (210,132 ) $ — $ 766,933 $ — $ 556,801 Cash flows from investing activities Capital expenditures for property and equipment (192 ) — — — (192 ) Acquisition of Northfield, net of cash acquired (1,068,336 ) — — — (1,068,336 ) Net cash provided by (used in) investing activities (1,068,528 ) — — — (1,068,528 ) Cash flows from financing activities Net borrowings (repayments) under bank credit facility 727,750 — — — 727,750 Deferred financing costs (17,490 ) — — — (17,490 ) Distributions paid (454,260 ) — — — (454,260 ) Cash received by Parent on behalf of Guarantor Subsidiaries 766,933 — (766,933 ) — — Net cash provided by (used in) financing activities 1,022,933 — (766,933 ) — 256,000 Cash flows from discontinued operations Cash flows from operating activities — — 23,406 23,406 Cash flows from investing activities — — 32,416 32,416 Cash flows from financing activities — — — — Net cash from discontinued operations — — 55,822 — 55,822 Cash and cash equivalents Net increase (decrease) for the period, including cash and cash equivalents classified as held for sale (255,727 ) — 55,822 — (199,905 ) Less: change in cash and cash equivalents classified as held for sale — — 55,822 — 55,822 Net increase (decrease) for the period (255,727 ) — — — (255,727 ) Balance, beginning of period 259,722 — — — 259,722 Balance, end of period $ 3,995 $ — $ — $ — $ 3,995 CONSOLIDATING STATEMENT OF OPERATIONS AND COMPREHENSIVE INCOME INFORMATION Year Ended December 31, 2017 Operating Co-Issuer Guarantor Eliminations Consolidated (in thousands) Revenues Rental revenue $ — $ — $ 675,089 $ — $ 675,089 Tenant reimbursements and other — — 90,606 — 90,606 — — 765,695 — 765,695 Expenses Depreciation — — 260,455 — 260,455 Property transactions, net — — 34,022 — 34,022 Reimbursable expenses — — 88,254 — 88,254 Amortization of above market lease, net — — 686 — 686 Acquisition-related expenses 17,304 — — — 17,304 General and administrative 12,189 — — — 12,189 29,493 — 383,417 — 412,910 (29,493 ) — 382,278 — 352,785 Equity in earnings of subsidiaries 377,372 — — (377,372 ) — Other income (expense) Interest income 3,907 — — — 3,907 Interest expense (184,175 ) — — — (184,175 ) Other (1,621 ) — — — (1,621 ) (181,889 ) — — — (181,889 ) Income (loss) before income taxes 165,990 — 382,278 (377,372 ) 170,896 Provision for income taxes — — (4,906 ) — (4,906 ) Net income (loss) $ 165,990 $ — $ 377,372 $ (377,372 ) $ 165,990 Other comprehensive income (loss) Net income (loss) 165,990 — 377,372 (377,372 ) 165,990 Unrealized gain on cash flow hedges 9,782 — — — 9,782 Comprehensive income (loss) $ 175,772 $ — $ 377,372 $ (377,372 ) $ 175,772 CONSOLIDATING STATEMENT OF CASH FLOWS INFORMATION Year Ended December 31, 2017 Operating Co-Issuer Guarantor Eliminations Consolidated (in thousands) Cash flows from operating activities Net cash provided by (used in) operating activities $ (198,925 ) $ — $ 681,503 $ — $ 482,578 Cash flows from investing activities Capital expenditures for property and equipment funded by Parent (488 ) — — — (488 ) MGM National Harbor transaction (462,500 ) — — — (462,500 ) Net cash used in investing activities (462,988 ) — — — (462,988 ) Cash flows from financing activities Proceeds from issuance of debt 350,000 — — — 350,000 Deferred financing costs (5,598 ) — — — (5,598 ) Repayment of assumed debt (425,000 ) — — — (425,000 ) Repayment of debt principal (41,875 ) — — — (41,875 ) Proceeds from purchase of Operating Partnership units by MGP 387,548 — — — 387,548 Distributions paid (385,435 ) — — — (385,435 ) Cash received by Parent on behalf of Guarantor Subsidiaries 681,503 — (681,503 ) — — Net cash provided by (used in) financing activities 561,143 — (681,503 ) — (120,360 ) Cash and cash equivalents Net decrease for the period (100,770 ) — — — (100,770 ) Balance, beginning of period 360,492 — — — 360,492 Balance, end of period $ 259,722 $ — $ — $ — $ 259,722 CONSOLIDATING STATEMENT OF OPERATIONS AND COMPREHENSIVE INCOME INFORMATION Year Ended December 31, 2016 Operating Co-Issuer Guarantor Eliminations Consolidated (in thousands) Revenues Rental revenue $ — $ — $ 419,239 $ — $ 419,239 Tenant reimbursements and other — — 48,309 — 48,309 — — 467,548 — 467,548 Expenses Depreciation — — 220,667 — 220,667 Property transactions, net — — 4,684 — 4,684 Reimbursable expenses — — 68,063 — 68,063 Amortization of above market lease, net — — 286 — 286 Acquisition-related expenses 10,178 — — — 10,178 General and administrative 9,896 — — — 9,896 20,074 — 293,700 — 313,774 (20,074 ) — 173,848 — 153,774 Equity in earnings of subsidiaries 171,584 — — (171,584 ) — Other income (expense) Interest income 774 — — — 774 Interest expense (116,212 ) — — — (116,212 ) Other (726 ) — — — (726 ) (116,164 ) — — — (116,164 ) Income (loss) before income taxes 35,346 — 173,848 (171,584 ) 37,610 Provision for income taxes — — (2,264 ) — (2,264 ) Net income (loss) $ 35,346 $ — $ 171,584 $ (171,584 ) $ 35,346 Other comprehensive income (loss) Net income (loss) 35,346 — 171,584 (171,584 ) 35,346 Unrealized gain on cash flow hedges 1,879 — — — 1,879 Comprehensive income (loss) $ 37,225 $ — $ 171,584 $ (171,584 ) $ 37,225 CONSOLIDATING STATEMENT OF CASH FLOWS INFORMATION Year Ended December 31, 2016 Operating Co-Issuer Guarantor Eliminations Consolidated (in thousands) Cash flows from operating activities Net cash provided by (used in) operating activities $ (99,884 ) $ — $ 397,665 $ — $ 297,781 Cash flows from investing activities Capital expenditures for property and equipment funded by Parent — — (138,987 ) — (138,987 ) Net cash used in investing activities — — (138,987 ) — (138,987 ) Cash flows from financing activities Proceeds from issuance of debt 3,700,000 — — — 3,700,000 Deferred financing costs (77,163 ) — — — (77,163 ) Repayment of bridge facilities (4,544,850 ) — — — (4,544,850 ) Repayment of debt principal (16,750 ) — — — (16,750 ) Proceeds from purchase of Operating Partnership units by MGP 1,132,468 — — — 1,132,468 Distributions paid (150,829 ) — — — (150,829 ) Cash received by Parent on behalf of Guarantor Subsidiaries 417,500 — (417,500 ) — — Net cash transfers from Parent — — 158,822 — 158,822 Net cash provided by (used in) financing activities 460,376 — (258,678 ) — 201,698 Cash and cash equivalents Net increase for the period 360,492 — — — 360,492 Balance, beginning of period — — — — — Balance, end of period $ 360,492 $ — $ — $ — $ 360,492

MGP Selected Quarterly Financia

MGP Selected Quarterly Financial Results (Unaudited)	12 Months Ended
	Dec. 31, 2018
Quarterly Financial Information Disclosure [Abstract]
MGP SELECTED QUARTERLY FINANCIAL RESULTS (UNAUDITED)	MGP SELECTED QUARTERLY FINANCIAL RESULTS (UNAUDITED) Quarter First Second Third Fourth Total (in thousands, except per share data) 2018 Revenues $ 215,839 $ 220,390 $ 216,659 $ 216,607 $ 869,495 Net income 58,169 48,059 69,923 68,551 244,702 Net income attributable to Class A shareholders 15,830 13,146 19,484 18,605 67,065 Net income per Class A share (basic) $ 0.22 $ 0.19 $ 0.27 $ 0.26 $ 0.94 Net income per Class A share (diluted) $ 0.22 $ 0.18 $ 0.27 $ 0.26 $ 0.94 2017 Revenues $ 183,899 $ 184,456 $ 182,798 $ 214,542 $ 765,695 Net income 46,692 43,875 43,700 31,723 165,990 Net income attributable to Class A shareholders 11,348 10,680 11,025 8,722 41,775 Net income per Class A share (basic) $ 0.20 $ 0.19 $ 0.18 $ 0.12 $ 0.68 Net income per Class A share (diluted) $ 0.20 $ 0.18 $ 0.18 $ 0.12 $ 0.67 Because net income per Class A share amounts are calculated using the weighted average number of basic and dilutive Class A shares outstanding during each quarter, the sum of the per share amounts for the four quarters does not equal the total net income per Class A share amounts for the year. The following sections list certain items affecting comparability of quarterly and year-to-date The Company’s results for Northfield OpCo for the year ended December 31, 2018 are presented as discontinued operations and the related assets and liabilities are classified as assets held for sale. The Company retained the real estate assets. See Note 3 for additional detail. In the fourth quarter of 2017, on October 5, 2017, MGM, MGP, the Operating Partnership, the Landlord and the Tenant completed the MGM National Harbor Transaction. The real estate assets related to MGM National Harbor were leased by the Landlord to the Tenant via an amendment to the Master Lease. As a result, the initial rent under the Master Lease increased by $95 million, $85.5 million of which relates to the base rent for the remainder of the 2017 lease year and the remaining $9.5 million of which relates to the percentage rent. Quarter First Second Third Fourth Total (in thousands, except per unit data) 2018 Revenues $ 215,839 $ 220,390 $ 216,659 $ 216,607 $ 869,495 Net income 58,169 48,059 69,923 68,551 244,702 Net income per Operating Partnership unit (basic) $ 0.22 $ 0.18 $ 0.26 $ 0.26 $ 0.92 Net income per Operating Partnership unit (diluted) $ 0.22 $ 0.18 $ 0.26 $ 0.26 $ 0.92 2017 Revenues $ 183,899 $ 184,456 $ 182,798 $ 214,542 $ 765,695 Net income 46,692 43,875 43,700 31,723 165,990 Net income per Operating Partnership unit (basic) $ 0.19 $ 0.18 $ 0.18 $ 0.12 $ 0.67 Net income per Operating Partnership unit (diluted) $ 0.19 $ 0.18 $ 0.18 $ 0.12 $ 0.66 See Note 14 for a discussion of items affecting comparability for the years ended December 31, 2018 and 2017, which are the same for the Operating Partnership.

Operating Partnership Selected

Operating Partnership Selected Quarterly Financial Results (Unaudited)	12 Months Ended
	Dec. 31, 2018
Quarterly Financial Information Disclosure [Abstract]
Operating Partnership Selected Quarterly Financial Results (Unaudited)	MGP SELECTED QUARTERLY FINANCIAL RESULTS (UNAUDITED) Quarter First Second Third Fourth Total (in thousands, except per share data) 2018 Revenues $ 215,839 $ 220,390 $ 216,659 $ 216,607 $ 869,495 Net income 58,169 48,059 69,923 68,551 244,702 Net income attributable to Class A shareholders 15,830 13,146 19,484 18,605 67,065 Net income per Class A share (basic) $ 0.22 $ 0.19 $ 0.27 $ 0.26 $ 0.94 Net income per Class A share (diluted) $ 0.22 $ 0.18 $ 0.27 $ 0.26 $ 0.94 2017 Revenues $ 183,899 $ 184,456 $ 182,798 $ 214,542 $ 765,695 Net income 46,692 43,875 43,700 31,723 165,990 Net income attributable to Class A shareholders 11,348 10,680 11,025 8,722 41,775 Net income per Class A share (basic) $ 0.20 $ 0.19 $ 0.18 $ 0.12 $ 0.68 Net income per Class A share (diluted) $ 0.20 $ 0.18 $ 0.18 $ 0.12 $ 0.67 Because net income per Class A share amounts are calculated using the weighted average number of basic and dilutive Class A shares outstanding during each quarter, the sum of the per share amounts for the four quarters does not equal the total net income per Class A share amounts for the year. The following sections list certain items affecting comparability of quarterly and year-to-date The Company’s results for Northfield OpCo for the year ended December 31, 2018 are presented as discontinued operations and the related assets and liabilities are classified as assets held for sale. The Company retained the real estate assets. See Note 3 for additional detail. In the fourth quarter of 2017, on October 5, 2017, MGM, MGP, the Operating Partnership, the Landlord and the Tenant completed the MGM National Harbor Transaction. The real estate assets related to MGM National Harbor were leased by the Landlord to the Tenant via an amendment to the Master Lease. As a result, the initial rent under the Master Lease increased by $95 million, $85.5 million of which relates to the base rent for the remainder of the 2017 lease year and the remaining $9.5 million of which relates to the percentage rent. Quarter First Second Third Fourth Total (in thousands, except per unit data) 2018 Revenues $ 215,839 $ 220,390 $ 216,659 $ 216,607 $ 869,495 Net income 58,169 48,059 69,923 68,551 244,702 Net income per Operating Partnership unit (basic) $ 0.22 $ 0.18 $ 0.26 $ 0.26 $ 0.92 Net income per Operating Partnership unit (diluted) $ 0.22 $ 0.18 $ 0.26 $ 0.26 $ 0.92 2017 Revenues $ 183,899 $ 184,456 $ 182,798 $ 214,542 $ 765,695 Net income 46,692 43,875 43,700 31,723 165,990 Net income per Operating Partnership unit (basic) $ 0.19 $ 0.18 $ 0.18 $ 0.12 $ 0.67 Net income per Operating Partnership unit (diluted) $ 0.19 $ 0.18 $ 0.18 $ 0.12 $ 0.66 See Note 14 for a discussion of items affecting comparability for the years ended December 31, 2018 and 2017, which are the same for the Operating Partnership.

Schedule III - Real Estate and

Schedule III - Real Estate and Accumulated Depreciation	12 Months Ended
	Dec. 31, 2018
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation Disclosure [Abstract]
SCHEDULE III - REAL ESTATE AND ACCUMULATED DEPRECIATION	SCHEDULE III — REAL ESTATE AND ACCUMULATED DEPRECIATION (in thousands) December 31, 2018 Acquisition Costs (a) Costs Capitalized Gross Amount (b) Property (c) Encumbrances Land Building, Land Building, Land Building, Total Accumulated Year (d) Useful Investment Properties: New York-New e $ 149,984 $ 484,001 $ — $ — $ 149,984 $ 484,536 $ 634,520 $ (296,527 ) 2016 g The Mirage e 1,017,562 760,222 — — 1,017,562 747,479 1,765,041 (484,617 ) 2016 g Mandalay Bay e 1,199,785 1,882,381 — — 1,199,785 1,871,540 3,071,325 (733,704 ) 2016 g Luxor e 440,685 710,796 — — 440,685 704,484 1,145,169 (350,834 ) 2016 g Excalibur e 814,805 342,685 — 43,945 814,805 384,036 1,198,841 (144,345 ) 2016 g Park MGM e 291,035 376,625 — 100,768 291,035 322,875 613,910 (87,453 ) 2016 g Beau Rivage e 104,945 561,457 — — 104,945 559,210 664,155 (258,113 ) 2016 g MGM Grand Detroit e 52,509 597,324 — — 52,509 597,324 649,833 (177,119 ) 2016 g Gold Strike Tunica e 3,609 179,146 — — 3,609 178,578 182,187 (88,475 ) 2016 g Borgata e 35,568 1,264,432 — — 35,568 1,254,782 1,290,350 (87,997 ) 2016 g MGM National Harbor — — 1,183,909 — — — 1,199,839 1,199,839 (83,837 ) 2017 g The Park e 33,026 101,353 — — 33,026 100,115 133,141 (13,638 ) 2016 g MGM Northfield Park (f) e 392,500 376,842 — — 392,500 376,842 769,342 (5,438 ) 2018 g 4,536,013 8,821,173 — 144,713 4,536,013 8,781,640 13,317,653 (2,812,097 ) Corporate Property: MGP Corporate Office — 488 — 192 — 681 681 (108 ) 2017 g $ 4,536,013 $ 8,821,661 $ — $ 144,905 $ 4,536,013 $ 8,782,321 $ 13,318,334 $ (2,812,205 ) (a) Represents the net carrying value of the IPO Properties on the IPO Date and the real estate assets of Borgata and MGM National Harbor on their respective acquisition dates by the Operating Partnership. (b) The aggregate cost of land, buildings and improvements for federal income tax purposes is approximately $9.4​​​​​​​ billion. (c) All of the properties are large-scale destination entertainment and gaming-related properties, with the exception of The Park and MGP Corporate Office. See “Item 1 — Business — Our Properties” for additional detail about our properties. (d) We have omitted the date of construction of our properties on the basis that compiling this disclosure on a site-by-site (e) The assets comprising these Properties collectively secure the entire amount of the Operating Partnership’s senior secured credit facility. (f) Reflects the real estate assets of MGM Northfield Park which were owned by the Company as of December 31, 2018 and were added to the Master Lease on April 1, 2019. Refer to Note 3 within the accompanying footnotes to the financial statements for further information. (g) Depreciation is computed based on the following estimated useful lives: Buildings and building improvements 20 to 40 years Land improvements 10 to 20 years Fixtures and integral equipment 3 to 20 years Reconciliation of Real Estate 2018 2017 2016 Balance at beginning of year $ 12,655,847 $ 11,468,170 $ 9,965,185 Additions (1) 788,850 1,273,776 1,511,390 Dispositions and write-offs (105,646 ) (86,905 ) (8,405 ) Other (20,717 ) 806 — Balance at end of year $ 13,318,334 $ 12,655,847 $ 11,468,170 (1) 2018 includes $769.3 million resulting from the Operating Partnership’s acquisition of the real estate assets of MGM Northfield Park. 2017 includes $ 1.2 1.3 Reconciliation of Accumulated Depreciation 2018 2017 2016 Balance at beginning of year $ (2,633,909 ) $ (2,388,492 ) $ (2,171,546 ) Depreciation expense (266,622 ) (260,455 ) (220,667 ) Dispositions and write-offs 85,327 52,883 3,721 Other 2,999 (37,845 ) — Balance at end of year $ (2,812,205 ) $ (2,633,909 ) $ (2,388,492 )

Basis of Presentation and Sum_2

Basis of Presentation and Summary of Significant Accounting Policies (Policies)	9 Months Ended	12 Months Ended
	Sep. 30, 2019	Dec. 31, 2018
Accounting Policies [Abstract]
Basis of presentation	Basis of presentation. The accompanying condensed consolidated financial statements and related notes should be read in conjunction with the audited financial statements and notes thereto included in the Company’s most recent Annual Report on Form 10-K.	Basis of presentation. For periods prior to the IPO Date, the accompanying combined and consolidated financial statements of MGP and the Operating Partnership represent the IPO Properties, which were controlled by MGM, and have been determined to be MGP’s and the Operating Partnership’s predecessor for accounting purposes (the “Predecessor”). The accompanying combined and consolidated financial statements include Predecessor financial statements that have been “carved out” of MGM’s consolidated financial statements and reflect significant assumptions and allocations. The financial statements do not fully reflect what the Predecessor’s results of operations, financial position and cash flows would have been if the Predecessor had been a stand-alone company during the periods presented. As a result, historical financial information is not necessarily indicative of the future results of operations, financial position and cash flows of MGP or the Operating Partnership. For periods subsequent to the IPO Date, the accompanying combined and consolidated financial statements of MGP and the Operating Partnership represent the results of operations, financial positions and cash flows of MGP and the Operating Partnership, including their respective subsidiaries. Certain reclassifications have been made to conform the prior period presentation. Property tax expense and property insurance expense were separately classified in prior periods and now are classified within “reimbursable expenses” in the accompanying combined and consolidated statements of operations.
Variable Interest Entities	Variable Interest Entities.
Principles of consolidation		Principles of consolidation. the exemption from providing certain of the required disclosures associated with investments in VIEs. The combined and consolidated financial statements of the Operating Partnership include the accounts of its wholly owned subsidiary, the Landlord, which owns the real estate, a VIE of which the Operating Partnership is the primary beneficiary. As of December 31, 2018, on a consolidated basis, the Landlord had total assets of $9.8 billion primarily related to its real estate assets and total liabilities of $247.5 million primarily related to its deferred revenue and above market lease liability. For entities not determined to be VIEs, the Company consolidates such entities in which the Company owns 100% of the equity. For entities in which the Company owns less than 100% of the equity interest, the Company consolidates the entity if it has the direct or indirect ability to control the entities’ activities based upon the terms of the respective entities’ ownership agreements. All intercompany balances and transactions are eliminated in consolidation.
Noncontrolling interest	Noncontrolling interest. MGM may tender its Operating Partnership units for redemption by the Operating Partnership in exchange for cash equal to the market price of MGP’s Class A shares at the time of redemption or for unregistered Class A shares on a one	Noncontrolling interest. MGM may tender its Operating Partnership units for redemption by the Operating Partnership in exchange for cash equal to the market price of MGP’s Class A shares at the time of redemption or for unregistered Class A shares on a one
Use of estimates		Use of estimates.
Real estate investments	Real estate investments. Although the Tenant is responsible for all capital expenditures during the term of the Master Lease, if, in the future, a deconsolidation event occurs, the Company will be required to pay the Tenant, should the Tenant so elect, for certain capital improvements that would not constitute “normal tenant improvements” in accordance with U.S. GAAP (“Non-Normal the 10-year Treasury 600 Non-Normal Non-Normal	Real estate investments. Although the Tenant is responsible for all capital expenditures during the term of the Master Lease, if, in the future, a deconsolidation event occurs, the Company will be required to pay the Tenant, should the Tenant so elect, for certain capital improvements that would not constitute “normal tenant improvements” in accordance with U.S. GAAP (“Non-Normal receive additional rent based on the 10-year Treasury 600 Non-Normal Non-Normal Inception-to-date, Non-Normal
Property and Equipment used in operations		Property and Equipment used in operations. The Company evaluates its long-lived assets for impairment based on its classification as held for sale or to be held and used. Several criteria must be met before an asset is classified as held for sale, including that management with the appropriate authority commits to a plan to sell the asset to a third-party at a reasonable price in relation to its fair value and is actively seeking a buyer. For assets held for sale, the Company recognizes the asset at the lower of carrying value or fair market value less costs to sell, as estimated based on comparable asset sales, offers received, or a discounted cash flow model. For assets to be held and used, the Company reviews for impairment whenever indicators of impairment exist. The Company then compares the estimated future cash flows of the asset, on an undiscounted basis, to the carrying value of the asset. If the undiscounted cash flows exceed the carrying value, no impairment is indicated. If the undiscounted cash flows do not exceed the carrying value, then an impairment charge is recorded based on the fair value of the asset, typically measured using a discounted cash flow model. All recognized impairment losses, whether for assets held for sale or assets to be held and used, are recorded as operating expenses. There were no Depreciation and property transactions. Buildings and building improvements 20 to 40 years Land improvements 10 to 20 years Furniture, fixtures and equipment 3 to 20 years Property transactions, net are comprised of transactions related to long-lived assets, such as normal losses on the disposition of assets.
Cash and cash equivalents		Cash and cash equivalents.
Deferred revenue	Deferred revenue. Non-Normal Non-Normal Ground lease and other reimbursable expenses. triple-net Revenue recognition. non-cancelable ten years four five be fixed and measurable. The difference between such rental revenue earned and the cash paid under the provisions of the Master Lease is recorded as deferred rent receivable and included as a component of tenant and other receivables, net or as deferred revenue if cash rent due exceeds rental revenue earned. Tenant reimbursement revenue and other reflects the amortization of deferred revenue relating to Non-Normal non-cash	Deferred revenue. Non-Normal Non-Normal Revenue recognition. non-cancelable ten years​​​​​​​ and all four five years​​​​​​​ Tenant reimbursement revenue arises from costs which the Company is the primary obligor that are required to be paid by the Tenant or reimbursed to the Company pursuant to the Master Lease. This revenue is recognized in the same periods as the expense is incurred. Northfield generates gaming, food, beverage and other revenue, which primarily consists of video lottery ​​​​​​​terminal (“VLT”) wager transactions and food and beverage transactions. The transaction price for a VLT wager is the difference between gaming wins and losses (net win). The Company accounts for VLT revenue on a portfolio basis given the similar characteristics of wagers by recognizing net win per gaming day versus on an individual wager basis. The transaction price of food and beverage contracts is the amount collected from customer or stand-alone selling price for such goods and services and is recorded when the delivery is made. Sales and usage-based taxes are excluded from revenues. Gaming, food, beverage and other revenue relate to the operations of Northfield and are classified as discontinued operations. Refer to Note 3 for further information.
Goodwill and other intangible assets		Goodwill and other intangible assets. No Accounting guidance provides entities the option to perform a qualitative assessment of goodwill and indefinite-lived intangible assets (commonly referred to as step zero) in order to determine whether further impairment testing is necessary. In performing the step zero analysis the Company considers macroeconomic conditions, industry and market considerations, current and forecasted financial performance, entity-specific events, and changes in the composition or carrying amount of net assets of reporting units for goodwill. In addition, the Company takes into consideration the amount of excess of fair value over carrying value determined in the last quantitative analysis that was performed, as well as the period of time that has passed since the last quantitative analysis. If the step zero analysis indicates that it is more likely than not that the fair value is less than its carrying amount, the entity would proceed to a quantitative analysis. Under the quantitative analysis, goodwill for relevant reporting units is tested for impairment using ​​​​​​​a discounted cash flow analysis based on the estimated future results of the Company’s reporting units discounted using market discount rates and market indicators of terminal year capitalization rates, and a market approach that utilizes business enterprise value multiples based on a range of multiples from the Company’s peer group. An impairment charge is recognized for the amount by which the carrying value exceeds the reporting unit’s fair value, not to exceed the total amount of goodwill allocated to that reporting unit. Under the qualitative analysis, the license rights are tested for impairment using a discounted cash flow approach. If the fair value of an indefinite-lived intangible asset is less than its carrying amount, an impairment loss is recognized equal to the difference.
Reimbursable expenses		Reimbursable expenses.
Acquisition-related expenses		Acquisition-related expenses.
General and administrative		General and administrative.
Net income per share and net income per unit		Net income per share. Net income per unit.
Deferred financing costs		Deferred financing costs.
Derivative financial instruments		Derivative financial instruments. Derivatives and Hedging
Fair value measurements	Fair value measurements. paid to transfer a liability in an orderly transaction between market participants at the measurement date and is measured according to a hierarchy that includes: Level 1 inputs, such as quoted prices in an active market; Level 2 inputs, which are observable inputs for similar assets; or Level 3 inputs, which are unobservable inputs. The Company used the following inputs in its fair value measurements: • Level 2 inputs for its long-term debt fair value disclosures. See Note 6; and • Level 2 inputs when measuring the fair value of its interest rate swaps. See Note 7.	Fair value measurements • Level 2 inputs for its long-term debt fair value disclosures. See Note 6; • Level 2 inputs when measuring the fair value of its interest rate swaps. See Note 7; and • Level 2 and Level 3 inputs when assessing the fair value of assets acquired and liabilities assumed during the Northfield Acquisition. See Note 3.
Reportable segment	Reportable segment.
Income tax provision	Income tax provision. year-to-date The Company accounts for income taxes under the asset and liability method, which requires the recognition of deferred tax assets and liabilities for the expected future tax consequences of events that have been included in the financial statements. Under this method, the Company determines deferred tax assets and liabilities on the basis of the differences between the financial statement and tax basis of assets and liabilities by using enacted tax rates in effect for the year in which the differences are expected to reverse. The effect of a change in tax rates on deferred tax assets and liabilities is recognized in income in the period that includes the enactment date. The Landlord is required to join in the filing of a New Jersey consolidated corporation business tax return under the New Jersey Casino Control Act and include in such return its income and expenses associated with its New Jersey assets and is thus subject to an entity level tax in New Jersey. Although the consolidated New Jersey return also includes MGM and certain of its subsidiaries, the Company is required to record New Jersey state income taxes in the accompanying financial statements as if the Landlord was taxed for state purposes on a stand-alone basis. The Company and MGM have entered into a tax sharing agreement providing for an allocation of taxes due in the consolidated New Jersey return. Pursuant to this agreement, the Landlord will only be responsible for New Jersey taxes on any gain that may be realized upon a future sale of the New Jersey assets resulting solely from an appreciation in value of such assets over their value on the date they were contributed to the Landlord by a subsidiary of MGM. MGM is responsible for all other taxes reported in the New Jersey consolidated return and, accordingly, the related income tax balances related to such taxes is reflected within noncontrolling interest within the accompanying financial statements. No amounts were due to MGM under the tax sharing agreement as of September 30, 2019 and December 31, 2018. Prior to April 1, 2019, the Company’s TRS owned the real estate assets and operations of Northfield and the Company recorded a tax provision on the income from the TRS operations. In connection with the Northfield OpCo Transaction, the TRS was liquidated on April 1, 2019 and the Company transferred the Northfield operations to a subsidiary of MGM and the Company retained the real estate. Consequently, the Company does not provide a tax provision on TRS operations after April 1, 2019.	Income taxes. been included in the financial statements. Under this method, the Company determines deferred tax assets and liabilities on the basis of the differences between the financial statement and tax bases of assets and liabilities by using enacted tax rates in effect for the ​​​​​​​year in which the differences are expected to reverse. The effect of a change in tax rates on deferred tax assets and liabilities is recognized in income in the period that includes the enactment date.
Concentrations of credit risk		Concentrations of credit risk.
Geographical risk		Geographical risk.
Lease incentive asset	Lease incentive asset. Non-Normal
Lessee leases	Lessee leases. For leases with terms greater than twelve months, the operating lease right-of-use
Recently issued accounting standards	Recently issued accounting standards. The Company is also a lessee in lease arrangements, primarily for land underlying certain of its properties. As a result of adoption, the Company recognized approximately $279.9 million of operating ROU assets and approximately $333.5 million of operating lease liabilities as of January 1, 2019.	Recently issued accounting standards. No. 2017-04, 2017-04”). 2017-04 2017-04 In August 2017, the FASB issued ASU No. 2017-12, Derivatives 2017-12”). 2017-12 2017-12 2017-12 In February 2018, the FASB issued ASC 842 “Leases (Topic 842),” which replaces the existing guidance in ASC 840, “Leases,” (“ASC 842”). ASC 842 is effective for fiscal years, and interim periods within those years, beginning after December 15, 2018. ASC 842 requires a dual approach for lessee accounting under which a lessee would account for leases as finance leases or operating leases. Both finance leases and operating leases will result in the lessee recognizing a right-of-use In May 2014, the FASB issued ASC 606, Revenue from Contracts with Customers (Topic 606) which outlines a new, single comprehensive model for entities to use in accounting for revenue arising from contracts with customers and supersedes most current revenue recognition guidance​​​​​​​, including industry-specific guidance. Under the standard, revenue is recognized when a customer obtains control of promised goods or services in an amount that reflects the consideration the entity expects to receive in exchange for those goods and services. The Company adopted ASC 606 on January 1, 2018 and it did not have a material​​​​​​​ impact on the Company’s financial statements.

Basis of Presentation and Sum_3

Basis of Presentation and Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2018
Accounting Policies [Abstract]
Useful Lives and Carrying Value of Property and Equipment Used in Operations	Depreciation expense is recognized over the useful lives of real estate investments and property and equipment used in operations applying the straight-line method over the following estimated useful lives, which are periodically reviewed: Buildings and building improvements 20 to 40 years Land improvements 10 to 20 years Furniture, fixtures and equipment 3 to 20 years

Acquisitions and dispositions -

Acquisitions and dispositions - (Tables)	9 Months Ended	12 Months Ended
	Sep. 30, 2019	Dec. 31, 2018
Business Combinations [Abstract]
Fair Value of Assets Acquired and Liabilities Assumed		The following table sets forth the preliminary purchase price allocation at July 6, 2018 (in thousands): Fair value of assets acquired and liabilities: Property and equipment used in operations $ 792,807 Cash and cash equivalents 35,831 Racing and gaming licenses 228,000 Customer list 25,000 Goodwill 17,915 Other assets 9,598 Other liabilities (38,786 ) $ 1,070,365
Results of discontinued operations	The results of the Northfield OpCo discontinued operations are summarized as follows: Nine Months Ended Three and Nine Months Ended 2019 (1) 2018 (2) Total revenues $ 67,841 $ 65,562 Total expenses (48,735 ) (48,997 ) Income from discontinued operations before income taxes 19,106 16,565 Provision for income taxes (2,890 ) (2,616 ) Income from discontinued operations, net of tax 16,216 13,949 Less: Income attributable to noncontrolling interests — discontinued operations (11,434 ) (10,231 ) Income from discontinued operations attributable to Class A shareholders $ 4,782 $ 3,718 (1) There was no income from discontinued operations for the three months ended September 30, 2019. (2) As Northfield was acquired on July 6, 2018, the results of the Northfield OpCo discontinued operations are the same for both the three and nine months ended September 30, 2018. December 31, 2018 (in thousands) Assets held for sale Property and equipment, used in operations, net $ 20,391 Cash and cash equivalents 55,822 Tenant and other receivables, net 7,322 Prepaid expenses and other assets 3,024 Goodwill 17,915 Other intangible assets, net 251,214 Assets held for sale $ 355,688 Liabilities related to assets held for sale Due to MGM Resorts International and affiliates $ 80 Accounts payable, accrued expenses and other liabilities 28,806 Deferred revenue 51 Liabilities related to assets held for sale $ 28,937	The results of the Northfield OpCo discontinued operations are summarized as follows: Year Ended December 31, (In thousands) Total revenues $ 132,949 Total expenses (97,330 ) Income for discontinued operations before income taxes 35,619 Provision for income tax (5,056 ) Income from discontinued operations, net of tax 30,563 Less: Net income attributable to noncontrolling interests — discontinued operations (22,417 ) Net income from discontinued operations $ 8,146 December 31, 2018 (In thousands) Assets held for sale Property and equipment, used in operations, net $ 20,391 Cash and cash equivalents 55,822 Tenant and other receivables, net 7,322 Prepaid expenses and other assets 3,024 Goodwill 17,915 Other intangible assets, net 251,214 Assets held for sale $ 355,688 Liabilities related to assets held for sale Due to MGM Resorts International and affiliates $ 80 Accounts payable, accrued expenses and other liabilities 28,806 Deferred revenue 51 Liabilities related to assets held for sale $ 28,937

Real Estate Investments - (Tabl

Real Estate Investments - (Tables)	9 Months Ended	12 Months Ended
	Sep. 30, 2019	Dec. 31, 2018
Real Estate [Abstract]
Carrying Value of Real Estate Investments	The carrying value of real estate investments is as follows: September 30, December 31, (in thousands) Land $ 4,631,013 $ 4,536,013 Buildings, building improvements, land improvements and integral equipment 9,281,926 8,782,321 13,912,939 13,318,334 Less: Accumulated depreciation (3,018,818 ) (2,812,205 ) $ 10,894,121 $ 10,506,129	The carrying value of real estate investments is as follows: December 31, 2018 2017 (in thousands) Land $ 4,536,013 $ 4,143,513 Buildings, building improvements, land improvements and integral equipment 8,782,321 8,512,334 13,318,334 12,655,847 Less: Accumulated depreciation (2,812,205 ) (2,633,909 ) $ 10,506,129 $ 10,021,938

Leases (Tables)

Leases (Tables)	9 Months Ended	12 Months Ended
	Sep. 30, 2019	Dec. 31, 2018
Leases [Abstract]
Lessor, Operating Lease Minimum Rental Payments	Under the Master Lease, future non-cancelable 10-year Year ending December 31, (in thousands) 2019 $ 236,515 2020 958,894 2021 976,262 2022 912,751 2023 890,126 Thereafter 1,922,713 $ 5,897,261
Future Noncancelable Minimum Rental Payments		Under the Master Lease, future non-cancelable 10-year Year ending December 31, (in thousands) 2019 $ 780,782 2020 794,907 2021 809,315 2022 757,060 2023 738,435 Thereafter 1,568,769 Total $ 5,449,268
Operating Lease Maturities	Maturities of operating lease liabilities were as follows: Year ending December 31, (in thousands) 2019 (excluding the nine months ended September 30, 2019) $ 4,541 2020 21,113 2021 24,996 2022 25,015 2023 24,875 Thereafter 1,357,650 Total future minimum lease payments 1,458,190 Less: Amount of lease payments representing interest (1,121,738 ) Total $ 336,452
Lease Cost	Other information related to the Company’s operating leases was as follows (in thousands, except for lease term and discount rate information): Supplemental balance sheet information Balance at September 30, 2019 Operating lease right-of-use $ 280,020 Operating lease liabilities 336,452 Weighted-average remaining lease term (years) 59 Weighted-average discount rate (%) 7 %

Debt (Tables)

Debt (Tables)	9 Months Ended	12 Months Ended
	Sep. 30, 2019	Dec. 31, 2018
Debt Disclosure [Abstract]
Debt	Debt consists of the following: September 30, December 31, 2019 2018 (in thousands) Senior secured credit facility: Senior secured term loan A facility $ 467,063 $ 470,000 Senior secured term loan B facility 1,785,250 1,799,125 Senior secured revolving credit facility — 550,000 $ 1,050 5.625 1,050,000 1,050,000 $ 500 4.50 500,000 500,000 $ 750 5.75 750,000 — $ 350 4.50 350,000 350,000 4,902,313 4,719,125 Less: Unamortized discount and debt issuance costs (54,905 ) (52,176 ) $ 4,847,408 $ 4,666,949	Debt consists of the following: December 31, 2018 2017 (in thousands) Senior secured credit facility: Senior secured term loan A facility $ 470,000 $ 273,750 Senior secured term loan B facility 1,799,125 1,817,625 Senior secured revolving credit facility 550,000 — $ 1,050 5.625 1,050,000 1,050,000 $ 500 4.50 500,000 500,000 $ 350 4.50 350,000 350,000 4,719,125 3,991,375 Less: Unamortized discount and debt issuance costs (52,176 ) (56,747 ) $ 4,666,949 $ 3,934,628
Maturities of the Principal Amount of Debt		Maturities of debt. Year ending December 31, (in thousands) 2019 $ 24,375 2020 30,250 2021 30,250 2022 30,250 2023 997,375 Thereafter 3,606,625 $ 4,719,125

Derivatives and Hedging Activ_2

Derivatives and Hedging Activities - (Tables)	9 Months Ended
	Sep. 30, 2019
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of Interest Rate Derivatives	The Operating Partnership is party to interest rate swaps, summarized in the table below, to mitigate the interest rate risk inherent in its senior credit facility. As of September 30, 2019, the Operating Partnership pays a weighted average fixed rate of 1.707% on a total notional amount of $1.5 billion. Notional Amount Weighted Average Fair Value Asset Effective Date Maturity Date (in thousands, except percentages) $300,000 1.158% $3,393 September 6, 2019 December 31, 2024 $1,200,000 1.844% $(9,926 ) May 3, 2017 November 30, 2021 400,000 2.252% (31,370 ) October 1, 2019 December 31, 2029 900,000 1.801% (13,274 ) November 30, 2021 December 31, 2024 $(54,570 )

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Provision for Income Taxes Attributable to Income (Loss) Before Income Taxes	The provision for income taxes attributable to income (loss) before income taxes is as follows: Year Ended December 31, 2018 2017 2016 (in thousands) Federal: Current $ — $ — $ — Deferred (1,142 ) — — Provision for federal income taxes on continuing operations $ (1,142 ) $ — $ — State: Current $ 5,746 $ 1,729 $ 2,156 Deferred 1,175 3,177 108 Provision for state income taxes on continuing operations $ 6,921 $ 4,906 $ 2,264
Reconciliation of Federal Income Tax Statutory Rate and Effective Tax Rate	A reconciliation of the federal income tax statutory rate and the Company’s effective tax rate on income from continuing operations is as follows: Year Ended December 31, 2018 2017 2016 Federal income tax statutory rate 21.0 % 35.0 % 35.0 % Federal valuation allowance — — — Income not subject to federal income tax (21.5 ) (35.0 ) (35.0 ) State taxes 3.1 2.9 6.0 Effective tax rate on income from continuing operations 2.6 % 2.9 % 6.0 %
Major Tax-Effected Components of Net Deferred Tax Liability	The major tax-effected December 31, 2018 2017 (in thousands) Deferred tax asset — federal and state Accruals, reserves and other $ 1,844 $ — Total deferred tax asset $ 1,844 $ — Deferred tax liability — federal and state Real estate investments, net $ (33,466 ) $ (28,544 ) Other intangible assets, net (2,012 ) — Total deferred tax liability (35,478 ) (28,544 ) Net deferred tax liability $ (33,634 ) $ (28,544 )

Shareholders' Equity and Part_2

Shareholders' Equity and Partners' Capital - (Tables)	9 Months Ended	12 Months Ended
	Sep. 30, 2019	Dec. 31, 2018
Equity [Abstract]
Changes in Accumulated Other Comprehensive Income	The following table summarizes the changes in accumulated other comprehensive income (loss) by component for the nine months ended September 30, 2019: Cash Flow Other Total (in thousands) Balance at January 1, 2019 $ 4,208 $ — $ 4,208 Other comprehensive loss before reclassifications (13,765 ) — (13,765 ) Amounts reclassified from accumulated other comprehensive income to interest expense (1,847 ) — (1,847 ) Empire City Transaction — (195 ) (195 ) Class A share issuances — 774 774 Park MGM Transaction — (16 ) (16 ) Other comprehensive income (loss) (15,612 ) 563 (15,049 ) Less: Other comprehensive loss attributable to noncontrolling interest 10,895 — 10,895 Balance at March 31, 2019 (509 ) 563 54 Other comprehensive loss before reclassifications (29,008 ) — (29,008 ) Amounts reclassified from accumulated other comprehensive income to interest expense (1,767 ) — (1,767 ) Class A share issuances — (105 ) (105 ) Northfield OpCo Transaction — 2 2 Other comprehensive loss (30,775 ) (103 ) (30,878 ) Less: Other comprehensive loss attributable to noncontrolling interest 21,128 — 21,128 Balance at June 30, 2019 (10,156 ) 460 (9,696 ) Other comprehensive loss before reclassifications (17,989 ) — (17,989 ) Amounts reclassified from accumulated other comprehensive loss to interest expense (1,281 ) — (1,281 ) Class A share issuances — (200 ) (200 ) Other comprehensive loss (19,270 ) (200 ) (19,470 ) Less: Other comprehensive loss attributable to noncontrolling interest 13,037 — 13,037 Balance at September 30, 2019 $ (16,389 ) $ 260 $ (16,129 )	The following table summarizes the changes in accumulated other comprehensive income: Cash Flow Hedges (in thousands) Balance at January 1, 2017 $ 445 Other comprehensive income before reclassifications 566 Amounts reclassified from accumulated other comprehensive income to interest expense 9,216 Other comprehensive income 9,782 Less: Other comprehensive (income) attributable to noncontrolling interest (7,119 ) Balance at December 31, 2017 3,108 Other comprehensive income before reclassifications 5,258 Amounts reclassified from accumulated other comprehensive income to interest expense (1,130 ) Other comprehensive income 4,128 Less: Other comprehensive (income) attributable to noncontrolling interest (3,028 ) Balance at December 31, 2018 $ 4,208

Net Income Per Class A Share -

Net Income Per Class A Share - (Tables)	9 Months Ended	12 Months Ended
	Sep. 30, 2019	Dec. 31, 2018
Earnings Per Share [Abstract]
Net Income and Number of Class A Shares Used in the Calculation of Basic and Diluted Income Per Share	The table below provides net income and the number of Class A shares used in the computations of “basic” net income per share, which utilizes the weighted-average number of Class A shares outstanding without regard to dilutive potential Class A shares, and “diluted” net income per share, which includes all such shares. Net income per share has not been presented for the Class B shareholder as the Class B share is not entitled to any economic rights in the Company. Three Months Ended Nine Months Ended 2019 2018 2019 2018 (in thousands, except share amounts) Numerator: Income from continuing operations $ 68,553 $ 55,974 $ 186,470 $ 162,202 Income from continuing operations attributable to noncontrolling interest (46,038 ) (40,208 ) (126,924 ) (117,460 ) Income from continuing operations attributable to Class A shares—basic and diluted 22,515 15,766 59,546 44,742 Income from discontinued operations — 13,949 16,216 13,949 Income from discontinued operations attributable to noncontrolling interest — (10,231 ) (11,434 ) (10,231 ) Income from discontinued operations attributable to Class A shares—basic and diluted — 3,718 4,782 3,718 Net income attributable to Class A shares—basic and diluted $ 22,515 $ 19,484 $ 64,328 $ 48,460 Denominator: Weighted average Class A shares outstanding (1) 93,165,443 71,005,052 89,440,552 70,991,129 Effect of dilutive (2)(3) 157,497 196,739 204,557 183,141 Weighted average Class A shares outstanding (1) 93,322,940 71,201,791 89,645,109 71,174,270 (1) Includes weighted average deferred share units granted to certain members of the board of directors. (2) No shares related to outstanding share-based compensation awards were excluded due to being antidilutive. (3) Diluted net income per Class A share does not assume conversion of the Operating Partnership units held by MGM as such conversion would be antidilutive. The table below provides net income and the number of Operating Partnership units used in the computations of “basic” net income per Operating Partnership unit, which utilizes the weighted-average number of Operating Partnership units outstanding without regard to dilutive potential Operating Partnership units, and “diluted” net income per Operating Partnership units, which includes all such Operating Partnership units. Three Months Ended September 30, Nine Months Ended September 30, 2019 2018 2019 2018 (in thousands, except share amounts) Numerator: Income from continuing operations $ 68,553 $ 55,974 $ 186,470 $ 162,202 Income from discontinued operations — 13,949 16,216 13,949 Net income—basic and diluted $ 68,553 $ 69,923 $ 202,686 $ 176,151 Denominator: Weighted average Operating Partnership units outstanding (1) 292,867,986 266,139,175 290,661,305 266,125,252 Effect of dilutive shares for diluted net income per Operating Partnership unit (2) 157,497 196,739 204,557 183,141 Weighted average Operating Partnership units outstanding (1) 293,025,483 266,335,914 290,865,862 266,308,393 (1) Includes weighted average deferred share units granted to certain members of the Board of Directors. (2) No shares related to outstanding share-based compensation awards were excluded due to being antidilutive.	The table below provides net income and the number of Class A shares used in the computations of “basic” net income per share, which utilizes the weighted-average number of Class A shares outstanding without regard to dilutive potential Class A shares, and “diluted” net income per share, which includes all such shares. Net income attributable to Class A shares, weighted average Class A shares outstanding and the effect of dilutive securities outstanding are presented for the period subsequent to the IPO Date. Net income per share has not been presented for the Class B shareholder as the Class B share is not entitled to any economic rights in the Company. Years ended April 25 — 2018 2017 2016 (in thousands, except share amounts) Numerator: Income from continuing operations, net of tax $ 214,139 $ 165,990 $ 35,346 Income from continuing operations attributable to noncontrolling interest (155,220 ) (124,215 ) (5,408 ) Income from continuing operations attributable to Class A shares — basic and diluted 58,919 41,775 29,938 Income from discontinued operations, net of tax 30,563 — — Income from discontinued operations attributable to noncontrolling interest (22,417 ) — — Income from discontinued operations attributable to Class A shares — basic and diluted 8,146 — — Net income attributable to Class A shares — basic and diluted $ 67,065 $ 41,775 $ 29,938 Denominator: Weighted average Class A shares outstanding (1) 70,997,589 61,733,136 57,502,158 Effect of dilutive shares for diluted net income per Class A share (2) 188,085 183,410 249,331 Weighted average Class A shares outstanding (1) 71,185,674 61,916,546 57,751,489 (1) Includes weighted average deferred share units granted to certain members of the board of directors. (2) No shares related to outstanding share-based compensation awards were excluded due to being antidilutive. (3) Diluted net income per Class A share does not assume conversion of the Operating Partnership units held by MGM as such conversion would be antidilutive. The table below provides net income and the number of Operating Partnership units used in the computations of “basic” net income per Operating Partnership unit, which utilizes the weighted-average number of Operating Partnership units outstanding without regard to dilutive potential Operating Partnership units, and “diluted” net income per Operating Partnership units, which includes all such Operating Partnership units. Net income attributable to Operating Partnership units, weighted average Operating Partnership units outstanding and the effect of dilutive securities outstanding are presented for the period subsequent to the IPO Date. Years ended April 25 — 2018 2017 2016 (in thousands, except share amounts) Numerator: Income from continuing operations, net of tax $ 214,139 $ 165,990 $ 119,729 Income from discontinued operations, net of tax 30,563 — — Net income — basic and diluted $ 244,702 $ 165,990 $ 119,729 Denominator: Weighted average Operating Partnership units outstanding (1) 266,131,712 249,451,258 232,181,070 Effect of dilutive shares for diluted net income per Operating Partnership unit (2) 188,085 183,410 249,331 Weighted average Operating Partnership units outstanding (1) 266,319,797 249,634,668 232,430,401 (1) Includes weighted average deferred share units granted to certain members of the Board of Directors. (2) No shares related to outstanding share-based compensation awards were excluded due to being antidilutive.

Net Income Per Operating Part_2

Net Income Per Operating Partnership Unit - (Tables)	9 Months Ended	12 Months Ended
	Sep. 30, 2019	Dec. 31, 2018
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Net Income and Number of Operating Partnership Units Used in the Calculation of Basic and Diluted Income Per Share	The table below provides net income and the number of Class A shares used in the computations of “basic” net income per share, which utilizes the weighted-average number of Class A shares outstanding without regard to dilutive potential Class A shares, and “diluted” net income per share, which includes all such shares. Net income per share has not been presented for the Class B shareholder as the Class B share is not entitled to any economic rights in the Company. Three Months Ended Nine Months Ended 2019 2018 2019 2018 (in thousands, except share amounts) Numerator: Income from continuing operations $ 68,553 $ 55,974 $ 186,470 $ 162,202 Income from continuing operations attributable to noncontrolling interest (46,038 ) (40,208 ) (126,924 ) (117,460 ) Income from continuing operations attributable to Class A shares—basic and diluted 22,515 15,766 59,546 44,742 Income from discontinued operations — 13,949 16,216 13,949 Income from discontinued operations attributable to noncontrolling interest — (10,231 ) (11,434 ) (10,231 ) Income from discontinued operations attributable to Class A shares—basic and diluted — 3,718 4,782 3,718 Net income attributable to Class A shares—basic and diluted $ 22,515 $ 19,484 $ 64,328 $ 48,460 Denominator: Weighted average Class A shares outstanding (1) 93,165,443 71,005,052 89,440,552 70,991,129 Effect of dilutive (2)(3) 157,497 196,739 204,557 183,141 Weighted average Class A shares outstanding (1) 93,322,940 71,201,791 89,645,109 71,174,270 (1) Includes weighted average deferred share units granted to certain members of the board of directors. (2) No shares related to outstanding share-based compensation awards were excluded due to being antidilutive. (3) Diluted net income per Class A share does not assume conversion of the Operating Partnership units held by MGM as such conversion would be antidilutive. The table below provides net income and the number of Operating Partnership units used in the computations of “basic” net income per Operating Partnership unit, which utilizes the weighted-average number of Operating Partnership units outstanding without regard to dilutive potential Operating Partnership units, and “diluted” net income per Operating Partnership units, which includes all such Operating Partnership units. Three Months Ended September 30, Nine Months Ended September 30, 2019 2018 2019 2018 (in thousands, except share amounts) Numerator: Income from continuing operations $ 68,553 $ 55,974 $ 186,470 $ 162,202 Income from discontinued operations — 13,949 16,216 13,949 Net income—basic and diluted $ 68,553 $ 69,923 $ 202,686 $ 176,151 Denominator: Weighted average Operating Partnership units outstanding (1) 292,867,986 266,139,175 290,661,305 266,125,252 Effect of dilutive shares for diluted net income per Operating Partnership unit (2) 157,497 196,739 204,557 183,141 Weighted average Operating Partnership units outstanding (1) 293,025,483 266,335,914 290,865,862 266,308,393 (1) Includes weighted average deferred share units granted to certain members of the Board of Directors. (2) No shares related to outstanding share-based compensation awards were excluded due to being antidilutive.	The table below provides net income and the number of Class A shares used in the computations of “basic” net income per share, which utilizes the weighted-average number of Class A shares outstanding without regard to dilutive potential Class A shares, and “diluted” net income per share, which includes all such shares. Net income attributable to Class A shares, weighted average Class A shares outstanding and the effect of dilutive securities outstanding are presented for the period subsequent to the IPO Date. Net income per share has not been presented for the Class B shareholder as the Class B share is not entitled to any economic rights in the Company. Years ended April 25 — 2018 2017 2016 (in thousands, except share amounts) Numerator: Income from continuing operations, net of tax $ 214,139 $ 165,990 $ 35,346 Income from continuing operations attributable to noncontrolling interest (155,220 ) (124,215 ) (5,408 ) Income from continuing operations attributable to Class A shares — basic and diluted 58,919 41,775 29,938 Income from discontinued operations, net of tax 30,563 — — Income from discontinued operations attributable to noncontrolling interest (22,417 ) — — Income from discontinued operations attributable to Class A shares — basic and diluted 8,146 — — Net income attributable to Class A shares — basic and diluted $ 67,065 $ 41,775 $ 29,938 Denominator: Weighted average Class A shares outstanding (1) 70,997,589 61,733,136 57,502,158 Effect of dilutive shares for diluted net income per Class A share (2) 188,085 183,410 249,331 Weighted average Class A shares outstanding (1) 71,185,674 61,916,546 57,751,489 (1) Includes weighted average deferred share units granted to certain members of the board of directors. (2) No shares related to outstanding share-based compensation awards were excluded due to being antidilutive. (3) Diluted net income per Class A share does not assume conversion of the Operating Partnership units held by MGM as such conversion would be antidilutive. The table below provides net income and the number of Operating Partnership units used in the computations of “basic” net income per Operating Partnership unit, which utilizes the weighted-average number of Operating Partnership units outstanding without regard to dilutive potential Operating Partnership units, and “diluted” net income per Operating Partnership units, which includes all such Operating Partnership units. Net income attributable to Operating Partnership units, weighted average Operating Partnership units outstanding and the effect of dilutive securities outstanding are presented for the period subsequent to the IPO Date. Years ended April 25 — 2018 2017 2016 (in thousands, except share amounts) Numerator: Income from continuing operations, net of tax $ 214,139 $ 165,990 $ 119,729 Income from discontinued operations, net of tax 30,563 — — Net income — basic and diluted $ 244,702 $ 165,990 $ 119,729 Denominator: Weighted average Operating Partnership units outstanding (1) 266,131,712 249,451,258 232,181,070 Effect of dilutive shares for diluted net income per Operating Partnership unit (2) 188,085 183,410 249,331 Weighted average Operating Partnership units outstanding (1) 266,319,797 249,634,668 232,430,401 (1) Includes weighted average deferred share units granted to certain members of the Board of Directors. (2) No shares related to outstanding share-based compensation awards were excluded due to being antidilutive.

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2018
Commitments and Contingencies Disclosure [Abstract]
Noncancelable Minimum Lease Payments Pursuant to Ground Leases	At December 31, 2018, the Company was obligated under non-cancelable non-cancelable Year ending December 31, (in thousands) 2019 $ 19,868 2020 21,113 2021 24,996 2022 25,015 2023 24,875 Thereafter 1,310,253 $ 1,426,120

Condensed Consolidating Finan_2

Condensed Consolidating Financial Information - (Tables)	9 Months Ended	12 Months Ended
	Sep. 30, 2019	Dec. 31, 2018
Condensed Financial Information Disclosure [Abstract]
Consolidating Balance Sheet Information	The guarantee of a subsidiary guarantor will be automatically released upon (i) a sale or other disposition (including by way of consolidation or merger) of the subsidiary guarantor, or the capital stock of the subsidiary guarantor; (ii) the sale or disposition of all or substantially all of the assets of the subsidiary guarantor; (iii) the designation in accordance with the indenture of a subsidiary guarantor as an unrestricted subsidiary; (iv) at such time as such subsidiary guarantor is no longer a subsidiary guarantor or other obligor with respect to any credit facilities or capital markets indebtedness of the Operating Partnership; or (v) defeasance or discharge of the notes. CONSOLIDATING BALANCE SHEET INFORMATION September 30, 2019 Operating Co-Issuer Guarantor Eliminations Consolidated (in thousands) Real estate investments, net $ 507 $ — $ 10,893,614 $ — $ 10,894,121 Lease incentive asset — — 532,186 — 532,186 Cash and cash equivalents 153,526 — — — 153,526 Tenant and other receivables, net 463 — — — 463 Intercompany 1,169,999 — — (1,169,999 ) — Prepaid expenses and other assets 15,730 — 11,683 — 27,413 Investments in subsidiaries 10,126,379 — — (10,126,379 ) — Above market lease, asset — — 41,834 — 41,834 Operating lease right-of-use 477 — 279,543 — 280,020 Total assets $ 11,467,081 $ — $ 11,758,860 $ (11,296,378 ) $ 11,929,563 Debt, net 4,847,408 — — — 4,847,408 Due to MGM Resorts International and affiliates 298 — — — 298 Intercompany — — 1,169,999 (1,169,999 ) — Accounts payable, accrued expenses and other liabilities 58,457 — 1,480 — 59,937 Accrued interest 37,407 — — — 37,407 Dividend and distribution payable 138,730 — — — 138,730 Deferred revenue — — 95,306 — 95,306 Deferred income taxes, net — — 29,721 — 29,721 Operating lease liabilities 477 — 335,975 — 336,452 Total liabilities 5,082,777 — 1,632,481 (1,169,999 ) 5,545,259 General partner — — — — — Limited partners 6,384,304 — 10,126,379 (10,126,379 ) 6,384,304 Total partners’ capital 6,384,304 — 10,126,379 (10,126,379 ) 6,384,304 Total liabilities and partners’ capital $ 11,467,081 $ — $ 11,758,860 $ (11,296,378 ) $ 11,929,563 CONSOLIDATING BALANCE SHEET INFORMATION December 31, 2018 Operating Co-Issuer Guarantor Eliminations Consolidated (in thousands) Real estate investments, net $ 572 $ — $ 10,505,557 $ — $ 10,506,129 Cash and cash equivalents 3,995 — — — 3,995 Tenant and other receivables, net 26 — 7,642 — 7,668 Intercompany 841,179 — — (841,179 ) — Prepaid expenses and other assets 34,813 — — — 34,813 Investments in subsidiaries 9,790,350 — — (9,790,350 ) — Above market lease, asset — — 43,014 — 43,014 Assets held for sale — — 355,688 — 355,688 Total assets $ 10,670,935 $ — $ 10,911,901 $ (10,631,529 ) $ 10,951,307 Debt, net 4,666,949 — — — 4,666,949 Due to MGM Resorts International and affiliates 227 — — — 227 Intercompany — — 841,179 (841,179 ) — Accounts payable, accrued expenses and other liabilities 13,102 — 7,694 — 20,796 Above market lease, liability — — 46,181 — 46,181 Accrued interest 26,096 — — — 26,096 Dividend and distribution payable 119,055 — — — 119,055 Deferred revenue — — 163,926 — 163,926 Deferred income taxes, net — — 33,634 — 33,634 Liabilities related to assets held for sale — — 28,937 — 28,937 Total liabilities 4,825,429 — 1,121,551 (841,179 ) 5,105,801 General partner — — — — — Limited partners 5,845,506 — 9,790,350 (9,790,350 ) 5,845,506 Total partners’ capital 5,845,506 — 9,790,350 (9,790,350 ) 5,845,506 Total liabilities and partners’ capital $ 10,670,935 $ — $ 10,911,901 $ (10,631,529 ) $ 10,951,307	CONSOLIDATING BALANCE SHEET INFORMATION December 31, 2018 Operating Guarantor Partnership Co-Issuer Subsidiaries Eliminations Consolidated (in thousands) Real estate investments, net $ 572 $ — $ 10,505,557 $ — $ 10,506,129 Cash and cash equivalents 3,995 — — — 3,995 Tenant and other receivables, net 26 — 7,642 — 7,668 Intercompany 841,179 — — (841,179 ) — Prepaid expenses and other assets 34,813 — — — 34,813 Investments in subsidiaries 9,790,350 — — (9,790,350 ) — Above market lease, asset — — 43,014 — 43,014 Assets held for sale — — 355,688 — 355,688 Total assets $ 10,670,935 $ — $ 10,911,901 $ (10,631,529 ) $ 10,951,307 Debt, net 4,666,949 — — — 4,666,949 Due to MGM Resorts International and affiliates 227 — — — 227 Intercompany — — 841,179 (841,179 ) — Accounts payable, accrued expenses, and other liabilities 13,102 — 7,694 — 20,796 Above market lease, liability — — 46,181 — 46,181 Accrued interest 26,096 — — — 26,096 Distribution payable 119,055 — — — 119,055 Deferred revenue — — 163,926 — 163,926 Deferred income taxes, net — — 33,634 — 33,634 Liabilities related to assets held for sale — — 28,937 — 28,937 Total liabilities 4,825,429 — 1,121,551 (841,179 ) 5,105,801 General partner — — — — — Limited partners 5,845,506 — 9,790,350 (9,790,350 ) 5,845,506 Total partners’ capital 5,845,506 — 9,790,350 (9,790,350 ) 5,845,506 Total liabilities and partners’ capital $ 10,670,935 $ — $ 10,911,901 $ (10,631,529 ) $ 10,951,307 CONSOLIDATING BALANCE SHEET INFORMATION December 31, 2017 Operating Co-Issuer Guarantor Eliminations Consolidated (in thousands) Real estate investments, net $ 488 $ — $ 10,021,450 $ — $ 10,021,938 Cash and cash equivalents 259,722 — — — 259,722 Tenant and other receivables, net 299 — 6,086 — 6,385 Intercompany 1,383,397 — — (1,383,397 ) — Prepaid expenses and other assets 18,487 — — — 18,487 Investments in subsidiaries 8,479,388 — — (8,479,388 ) — Above market lease, asset — — 44,588 — 44,588 Total assets $ 10,141,781 $ — $ 10,072,124 $ (9,862,785 ) $ 10,351,120 Debt, net 3,934,628 — — — 3,934,628 Due to MGM Resorts International and affiliates 962 — — — 962 Intercompany — — 1,383,397 (1,383,397 ) — Accounts payable, accrued expenses, and other liabilities 4,154 — 6,086 — 10,240 Above market lease, liability — — 47,069 — 47,069 Accrued interest 22,565 — — — 22,565 Distribution payable 111,733 — — — 111,733 Deferred revenue — — 127,640 — 127,640 Deferred income taxes, net — — 28,544 — 28,544 Total liabilities 4,074,042 — 1,592,736 (1,383,397 ) 4,283,381 General partner — — — — — Limited partners 6,067,739 — 8,479,388 (8,479,388 ) 6,067,739 Total partners’ capital 6,067,739 — 8,479,388 (8,479,388 ) 6,067,739 Total liabilities and partners’ capital $ 10,141,781 $ — $ 10,072,124 $ (9,862,785 ) $ 10,351,120
Consolidating Statement of Operations and Comprehensive Income Information	CONSOLIDATING STATEMENT OF OPERATIONS AND COMPREHENSIVE INCOME INFORMATION Three Months Ended September 30, 2019 Operating Co-Issuer Guarantor Eliminations Consolidated (in thousands) Revenues Rental revenue $ — $ — $ 219,847 $ — $ 219,847 Tenant reimbursements and other — — 6,164 — 6,164 Total revenues — — 226,011 — 226,011 Expenses Depreciation 22 — 71,935 — 71,957 Property transactions, net — — 9,921 — 9,921 Ground lease and other reimbursable expenses — — 5,920 — 5,920 Acquisition-related expenses 92 — — — 92 General and administrative 4,476 — — — 4,476 Total expenses 4,590 — 87,776 — 92,366 Equity in earnings of subsidiaries 136,256 — — (136,256 ) — Other income (expense) Interest income 241 — — — 241 Interest expense (63,048 ) — — — (63,048 ) Other (306 ) — — — (306 ) (63,113 ) — — — (63,113 ) Income before income taxes 68,553 — 138,235 (136,256 ) 70,532 Provision for income taxes — — (1,979 ) — (1,979 ) Net income $ 68,553 $ — $ 136,256 $ (136,256 ) $ 68,553 Other comprehensive income Net income $ 68,553 $ — $ 136,256 $ (136,256 ) $ 68,553 Unrealized loss on cash flow hedges, net (19,270 ) — — — (19,270 ) Comprehensive income $ 49,283 $ — $ 136,256 $ (136,256 ) $ 49,283 CONSOLIDATING STATEMENT OF OPERATIONS AND COMPREHENSIVE INCOME INFORMATION Three Months Ended September 30, 2018 Operating Co-Issuer Guarantor Eliminations Consolidated (in thousands) Revenues Rental revenue $ — $ — $ 186,564 $ — $ 186,564 Tenant reimbursements and other — — 30,095 — 30,095 Total revenues — — 216,659 — 216,659 Expenses Depreciation 45 — 63,423 — 63,468 Property transactions, net — — 339 — 339 Ground lease and other reimbursable expenses — — 29,168 — 29,168 Amortization of above market lease, net — — 171 — 171 Acquisition-related expenses 1,931 — — — 1,931 General and administrative 3,358 — — — 3,358 Total expenses 5,334 — 93,101 — 98,435 Equity in earnings of subsidiaries 129,568 — — (129,568 ) — Other income (expense) Interest income 5,452 — — (5,289 ) 163 Interest expense (58,743 ) — (5,289 ) 5,289 (58,743 ) Other (1,020 ) — — — (1,020 ) (54,311 ) — (5,289 ) — (59,600 ) Income from continuing operations before income taxes 69,923 — 118,269 (129,568 ) 58,624 Provision for income taxes — — (2,650 ) — (2,650 ) Income from continuing operations, net of tax 69,923 — 115,619 (129,568 ) 55,974 Income from discontinued operations, net of tax — — 13,949 — 13,949 Net income $ 69,923 $ — $ 129,568 $ (129,568 ) $ 69,923 Other comprehensive income Net income $ 69,923 $ — $ 129,568 $ (129,568 ) $ 69,923 Unrealized gain on cash flow hedges, net 4,736 — — — 4,736 Comprehensive income $ 74,659 $ — $ 129,568 $ (129,568 ) $ 74,659 CONSOLIDATING STATEMENT OF OPERATIONS AND COMPREHENSIVE INCOME INFORMATION Nine Months Ended September 30, 2019 Operating Co-Issuer Guarantor Eliminations Consolidated (in thousands) Revenues Rental revenue $ — $ — $ 636,575 $ — $ 636,575 Tenant reimbursements and other — — 18,618 — 18,618 Total revenues — — 655,193 — 655,193 Expenses Depreciation 65 — 222,997 — 223,062 Property transactions, net — — 11,344 — 11,344 Ground lease and other reimbursable expenses — — 17,760 — 17,760 Acquisition-related expenses 8,891 — — — 8,891 General and administrative 12,305 — — — 12,305 Total expenses 21,261 — 252,101 — 273,362 Equity in earnings of subsidiaries 409,665 — — (409,665 ) — Other income (expense) Interest income 7,806 — — (5,617 ) 2,189 Interest expense (190,973 ) — (5,617 ) 5,617 (190,973 ) Other (806 ) — — — (806 ) (183,973 ) — (5,617 ) — (189,590 ) Income from continuing operations before income taxes 204,431 — 397,475 (409,665 ) 192,241 Provision for income taxes (1,745 ) — (4,026 ) — (5,771 ) Income from continuing operations, net of tax 202,686 — 393,449 (409,665 ) 186,470 Income from discontinued operations, net of tax — — 16,216 — 16,216 Net income $ 202,686 $ — $ 409,665 $ (409,665 ) $ 202,686 Other comprehensive income Net income $ 202,686 $ — $ 409,665 $ (409,665 ) $ 202,686 Unrealized loss on cash flow hedges, net (65,657 ) — — — (65,657 ) Comprehensive income $ 137,029 $ — $ 409,665 $ (409,665 ) $ 137,029 CONSOLIDATING STATEMENT OF OPERATIONS AND COMPREHENSIVE INCOME INFORMATION Nine Months Ended September 30, 2018 Operating Co-Issuer Guarantor Eliminations Consolidated (in thousands) Revenues Rental revenue $ — $ — $ 559,690 $ — $ 559,690 Tenant reimbursements and other — — 93,198 — 93,198 Total revenues — — 652,888 — 652,888 Expenses Depreciation 87 — 199,846 — 199,933 Property transactions, net — — 18,851 — 18,851 Ground lease and other reimbursable expenses — — 90,435 — 90,435 Amortization of above market lease, net — — 514 — 514 Acquisition-related expenses 4,603 — — — 4,603 General and administrative 10,021 — — — 10,021 Total expenses 14,711 — 309,646 — 324,357 Equity in earnings of subsidiaries 346,758 — — (346,758 ) — Other income (expense) Interest income 7,762 — — (5,289 ) 2,473 Interest expense (157,249 ) — (5,289 ) 5,289 (157,249 ) Other (6,409 ) — — — (6,409 ) (155,896 ) — (5,289 ) — (161,185 ) Income from continuing operations before income taxes 176,151 — 337,953 (346,758 ) 167,346 Provision for income taxes — — (5,144 ) — (5,144 ) Income from continuing operations, net of tax 176,151 — 332,809 (346,758 ) 162,202 Income from discontinued operations, net of tax — — 13,949 — 13,949 Net income $ 176,151 $ — $ 346,758 $ (346,758 ) $ 176,151 Other comprehensive income Net income $ 176,151 $ — $ 346,758 $ (346,758 ) $ 176,151 Unrealized gain on cash flow hedges, net 27,372 — — — 27,372 Comprehensive income $ 203,523 $ — $ 346,758 $ (346,758 ) $ 203,523	CONSOLIDATING STATEMENT OF OPERATIONS AND COMPREHENSIVE INCOME INFORMATION Year Ended December 31, 2018 Operating Co-Issuer Guarantor Eliminations Consolidated (in thousands) Revenues Rental revenue $ — $ — $ 746,253 $ — $ 746,253 Tenant reimbursements and other — — 123,242 — 123,242 — — 869,495 — 869,495 Expenses Depreciation 108 — 266,514 — 266,622 Property transactions, net — — 20,319 — 20,319 Reimbursable expenses — — 119,531 — 119,531 Amortization of above market lease, net — — 686 — 686 Acquisition-related expenses 6,149 — — — 6,149 General and administrative 16,048 — — — 16,048 22,305 — 407,050 — 429,355 (22,305 ) — 462,445 — 440,140 Equity in earnings of subsidiaries 476,353 — — (476,353 ) — Other income (expense) Interest income 13,377 — — (10,876 ) 2,501 Interest expense (215,532 ) — (10,876 ) 10,876 (215,532 ) Other (7,191 ) — — — (7,191 ) (209,346 ) — (10,876 ) — (220,222 ) Income (loss) from continuing operations before income taxes 244,702 — 451,569 (476,353 ) 219,918 Provision for income taxes — — (5,779 ) — (5,779 ) Income from continuing operations, net of tax $ 244,702 $ — $ 445,790 $ (476,353 ) $ 214,139 Income from discontinued operations, net of tax (Note 3) — — 30,563 — 30,563 Net income (loss) $ 244,702 $ — $ 476,353 $ (476,353 ) $ 244,702 Other comprehensive income (loss) Net income (loss) 244,702 — 476,353 (476,353 ) 244,702 Unrealized gain on cash flow hedges 4,128 — — — 4,128 Comprehensive income (loss) $ 248,830 $ — $ 476,353 $ (476,353 ) $ 248,830 CONSOLIDATING STATEMENT OF OPERATIONS AND COMPREHENSIVE INCOME INFORMATION Year Ended December 31, 2017 Operating Co-Issuer Guarantor Eliminations Consolidated (in thousands) Revenues Rental revenue $ — $ — $ 675,089 $ — $ 675,089 Tenant reimbursements and other — — 90,606 — 90,606 — — 765,695 — 765,695 Expenses Depreciation — — 260,455 — 260,455 Property transactions, net — — 34,022 — 34,022 Reimbursable expenses — — 88,254 — 88,254 Amortization of above market lease, net — — 686 — 686 Acquisition-related expenses 17,304 — — — 17,304 General and administrative 12,189 — — — 12,189 29,493 — 383,417 — 412,910 (29,493 ) — 382,278 — 352,785 Equity in earnings of subsidiaries 377,372 — — (377,372 ) — Other income (expense) Interest income 3,907 — — — 3,907 Interest expense (184,175 ) — — — (184,175 ) Other (1,621 ) — — — (1,621 ) (181,889 ) — — — (181,889 ) Income (loss) before income taxes 165,990 — 382,278 (377,372 ) 170,896 Provision for income taxes — — (4,906 ) — (4,906 ) Net income (loss) $ 165,990 $ — $ 377,372 $ (377,372 ) $ 165,990 Other comprehensive income (loss) Net income (loss) 165,990 — 377,372 (377,372 ) 165,990 Unrealized gain on cash flow hedges 9,782 — — — 9,782 Comprehensive income (loss) $ 175,772 $ — $ 377,372 $ (377,372 ) $ 175,772 CONSOLIDATING STATEMENT OF OPERATIONS AND COMPREHENSIVE INCOME INFORMATION Year Ended December 31, 2016 Operating Co-Issuer Guarantor Eliminations Consolidated (in thousands) Revenues Rental revenue $ — $ — $ 419,239 $ — $ 419,239 Tenant reimbursements and other — — 48,309 — 48,309 — — 467,548 — 467,548 Expenses Depreciation — — 220,667 — 220,667 Property transactions, net — — 4,684 — 4,684 Reimbursable expenses — — 68,063 — 68,063 Amortization of above market lease, net — — 286 — 286 Acquisition-related expenses 10,178 — — — 10,178 General and administrative 9,896 — — — 9,896 20,074 — 293,700 — 313,774 (20,074 ) — 173,848 — 153,774 Equity in earnings of subsidiaries 171,584 — — (171,584 ) — Other income (expense) Interest income 774 — — — 774 Interest expense (116,212 ) — — — (116,212 ) Other (726 ) — — — (726 ) (116,164 ) — — — (116,164 ) Income (loss) before income taxes 35,346 — 173,848 (171,584 ) 37,610 Provision for income taxes — — (2,264 ) — (2,264 ) Net income (loss) $ 35,346 $ — $ 171,584 $ (171,584 ) $ 35,346 Other comprehensive income (loss) Net income (loss) 35,346 — 171,584 (171,584 ) 35,346 Unrealized gain on cash flow hedges 1,879 — — — 1,879 Comprehensive income (loss) $ 37,225 $ — $ 171,584 $ (171,584 ) $ 37,225
Consolidating Statement of Cash Flows Information	CONSOLIDATING STATEMENT OF CASH FLOWS INFORMATION Nine Months Ended September 30, 2019 Operating Co-Issuer Guarantor Eliminations Consolidated (in thousands) Cash flows from operating activities Net cash provided by (used in) operating activities $ (762,230 ) $ — $ 677,713 $ — $ (84,517 ) Cash flows from investing activities Proceeds from Northfield OpCo Transaction 3,779 — — — 3,779 Net cash provided by investing activities 3,779 — — — 3,779 Cash flows from financing activities Net repayments under bank credit facility (566,813 ) — — — (566,813 ) Proceeds from issuance of debt 750,000 — — — 750,000 Deferred financing costs (9,983 ) — — — (9,983 ) Repayment of assumed bridge facility (245,950 ) — — — (245,950 ) Issuance of Operating Partnership units 699,362 — — — 699,362 Distributions paid (395,005 ) — — — (395,005 ) Cash received by Parent on behalf of Guarantor Subsidiaries, net 677,713 — (677,713 ) — — Other (1,342 ) — — — (1,342 ) Net cash provided by (used in) financing activities 907,982 — (677,713 ) — 230,269 Cash flows from discontinued operations, net Cash flows provided by operating activities, net — — 15,591 — 15,591 Cash flows used in investing activities, net — — (12 ) — (12 ) Cash flows used in financing activities, net — — (37,900 ) — (37,900 ) Net cash used in discontinued operations — — (22,321 ) — (22,321 ) Change in cash and cash equivalents classified as assets held for sale — — (22,321 ) — (22,321 ) Cash and cash equivalents Net increase for the period 149,531 — — — 149,531 Balance, beginning of period 3,995 — — — 3,995 Balance, end of period $ 153,526 $ — $ — $ — $ 153,526 CONSOLIDATING STATEMENT OF CASH FLOWS INFORMATION Nine Months Ended September 30, 2018 Operating Co-Issuer Guarantor Eliminations Consolidated (in thousands) Cash flows from operating activities Net cash provided by (used in) operating activities $ (149,511 ) $ — $ 574,348 $ — $ 424,837 Cash flows from investing activities Capital expenditures for property and equipment (191 ) — — — (191 ) Acquisition of Northfield (1,068,337 ) — — (1,068,337 ) Net cash used in investing activities (1,068,528 ) — — — (1,068,528 ) Cash flows from financing activities Net borrowings under bank credit facility 747,375 — — — 747,375 Deferred financing costs (17,490 ) — — — (17,490 ) Distributions paid (337,865 ) — — — (337,865 ) Cash received by Parent on behalf of Guarantor Subsidiaries 574,348 — (574,348 ) — — Net cash provided by (used in) financing activities 966,368 — (574,348 ) — 392,020 Cash flows from discontinued operations, net Cash flows provided by operating activities, net — — 8,250 — 8,250 Cash flows provided by investing activities, net — — 33,199 — 33,199 Cash flows used in financing activities, net — — — — — Net cash provided by discontinued operations — — 41,449 — 41,449 Cash flows from discontinued operations, net Change in cash and cash equivalents classified as assets held for sale — — 41,449 — 41,449 Cash and cash equivalents Net decrease for the period (251,671 ) — — — (251,671 ) Balance, beginning of period 259,722 — — — 259,722 Balance, end of period $ 8,051 $ — $ — $ — $ 8,051	CONSOLIDATING STATEMENT OF CASH FLOWS INFORMATION Year Ended December 31, 2018 Operating Co-Issuer Guarantor Eliminations Consolidated (in thousands) Cash flows from operating activities Net cash provided by (used in) operating activities $ (210,132 ) $ — $ 766,933 $ — $ 556,801 Cash flows from investing activities Capital expenditures for property and equipment (192 ) — — — (192 ) Acquisition of Northfield, net of cash acquired (1,068,336 ) — — — (1,068,336 ) Net cash provided by (used in) investing activities (1,068,528 ) — — — (1,068,528 ) Cash flows from financing activities Net borrowings (repayments) under bank credit facility 727,750 — — — 727,750 Deferred financing costs (17,490 ) — — — (17,490 ) Distributions paid (454,260 ) — — — (454,260 ) Cash received by Parent on behalf of Guarantor Subsidiaries 766,933 — (766,933 ) — — Net cash provided by (used in) financing activities 1,022,933 — (766,933 ) — 256,000 Cash flows from discontinued operations Cash flows from operating activities — — 23,406 23,406 Cash flows from investing activities — — 32,416 32,416 Cash flows from financing activities — — — — Net cash from discontinued operations — — 55,822 — 55,822 Cash and cash equivalents Net increase (decrease) for the period, including cash and cash equivalents classified as held for sale (255,727 ) — 55,822 — (199,905 ) Less: change in cash and cash equivalents classified as held for sale — — 55,822 — 55,822 Net increase (decrease) for the period (255,727 ) — — — (255,727 ) Balance, beginning of period 259,722 — — — 259,722 Balance, end of period $ 3,995 $ — $ — $ — $ 3,995 CONSOLIDATING STATEMENT OF CASH FLOWS INFORMATION Year Ended December 31, 2017 Operating Co-Issuer Guarantor Eliminations Consolidated (in thousands) Cash flows from operating activities Net cash provided by (used in) operating activities $ (198,925 ) $ — $ 681,503 $ — $ 482,578 Cash flows from investing activities Capital expenditures for property and equipment funded by Parent (488 ) — — — (488 ) MGM National Harbor transaction (462,500 ) — — — (462,500 ) Net cash used in investing activities (462,988 ) — — — (462,988 ) Cash flows from financing activities Proceeds from issuance of debt 350,000 — — — 350,000 Deferred financing costs (5,598 ) — — — (5,598 ) Repayment of assumed debt (425,000 ) — — — (425,000 ) Repayment of debt principal (41,875 ) — — — (41,875 ) Proceeds from purchase of Operating Partnership units by MGP 387,548 — — — 387,548 Distributions paid (385,435 ) — — — (385,435 ) Cash received by Parent on behalf of Guarantor Subsidiaries 681,503 — (681,503 ) — — Net cash provided by (used in) financing activities 561,143 — (681,503 ) — (120,360 ) Cash and cash equivalents Net decrease for the period (100,770 ) — — — (100,770 ) Balance, beginning of period 360,492 — — — 360,492 Balance, end of period $ 259,722 $ — $ — $ — $ 259,722 CONSOLIDATING STATEMENT OF CASH FLOWS INFORMATION Year Ended December 31, 2016 Operating Co-Issuer Guarantor Eliminations Consolidated (in thousands) Cash flows from operating activities Net cash provided by (used in) operating activities $ (99,884 ) $ — $ 397,665 $ — $ 297,781 Cash flows from investing activities Capital expenditures for property and equipment funded by Parent — — (138,987 ) — (138,987 ) Net cash used in investing activities — — (138,987 ) — (138,987 ) Cash flows from financing activities Proceeds from issuance of debt 3,700,000 — — — 3,700,000 Deferred financing costs (77,163 ) — — — (77,163 ) Repayment of bridge facilities (4,544,850 ) — — — (4,544,850 ) Repayment of debt principal (16,750 ) — — — (16,750 ) Proceeds from purchase of Operating Partnership units by MGP 1,132,468 — — — 1,132,468 Distributions paid (150,829 ) — — — (150,829 ) Cash received by Parent on behalf of Guarantor Subsidiaries 417,500 — (417,500 ) — — Net cash transfers from Parent — — 158,822 — 158,822 Net cash provided by (used in) financing activities 460,376 — (258,678 ) — 201,698 Cash and cash equivalents Net increase for the period 360,492 — — — 360,492 Balance, beginning of period — — — — — Balance, end of period $ 360,492 $ — $ — $ — $ 360,492

MGP Selected Quarterly Financ_2

MGP Selected Quarterly Financial Results (Unaudited) (Tables)	12 Months Ended
	Dec. 31, 2018
Quarterly Financial Information Disclosure [Abstract]
Quarterly Financial Information	Quarter First Second Third Fourth Total (in thousands, except per share data) 2018 Revenues $ 215,839 $ 220,390 $ 216,659 $ 216,607 $ 869,495 Net income 58,169 48,059 69,923 68,551 244,702 Net income attributable to Class A shareholders 15,830 13,146 19,484 18,605 67,065 Net income per Class A share (basic) $ 0.22 $ 0.19 $ 0.27 $ 0.26 $ 0.94 Net income per Class A share (diluted) $ 0.22 $ 0.18 $ 0.27 $ 0.26 $ 0.94 2017 Revenues $ 183,899 $ 184,456 $ 182,798 $ 214,542 $ 765,695 Net income 46,692 43,875 43,700 31,723 165,990 Net income attributable to Class A shareholders 11,348 10,680 11,025 8,722 41,775 Net income per Class A share (basic) $ 0.20 $ 0.19 $ 0.18 $ 0.12 $ 0.68 Net income per Class A share (diluted) $ 0.20 $ 0.18 $ 0.18 $ 0.12 $ 0.67 Quarter First Second Third Fourth Total (in thousands, except per unit data) 2018 Revenues $ 215,839 $ 220,390 $ 216,659 $ 216,607 $ 869,495 Net income 58,169 48,059 69,923 68,551 244,702 Net income per Operating Partnership unit (basic) $ 0.22 $ 0.18 $ 0.26 $ 0.26 $ 0.92 Net income per Operating Partnership unit (diluted) $ 0.22 $ 0.18 $ 0.26 $ 0.26 $ 0.92 2017 Revenues $ 183,899 $ 184,456 $ 182,798 $ 214,542 $ 765,695 Net income 46,692 43,875 43,700 31,723 165,990 Net income per Operating Partnership unit (basic) $ 0.19 $ 0.18 $ 0.18 $ 0.12 $ 0.67 Net income per Operating Partnership unit (diluted) $ 0.19 $ 0.18 $ 0.18 $ 0.12 $ 0.66

Operating Partnership Selecte_2

Operating Partnership Selected Quarterly Financial Results (Unaudited) (Tables)	12 Months Ended
	Dec. 31, 2018
Quarterly Financial Information Disclosure [Abstract]
Quarterly Financial Information	Quarter First Second Third Fourth Total (in thousands, except per share data) 2018 Revenues $ 215,839 $ 220,390 $ 216,659 $ 216,607 $ 869,495 Net income 58,169 48,059 69,923 68,551 244,702 Net income attributable to Class A shareholders 15,830 13,146 19,484 18,605 67,065 Net income per Class A share (basic) $ 0.22 $ 0.19 $ 0.27 $ 0.26 $ 0.94 Net income per Class A share (diluted) $ 0.22 $ 0.18 $ 0.27 $ 0.26 $ 0.94 2017 Revenues $ 183,899 $ 184,456 $ 182,798 $ 214,542 $ 765,695 Net income 46,692 43,875 43,700 31,723 165,990 Net income attributable to Class A shareholders 11,348 10,680 11,025 8,722 41,775 Net income per Class A share (basic) $ 0.20 $ 0.19 $ 0.18 $ 0.12 $ 0.68 Net income per Class A share (diluted) $ 0.20 $ 0.18 $ 0.18 $ 0.12 $ 0.67 Quarter First Second Third Fourth Total (in thousands, except per unit data) 2018 Revenues $ 215,839 $ 220,390 $ 216,659 $ 216,607 $ 869,495 Net income 58,169 48,059 69,923 68,551 244,702 Net income per Operating Partnership unit (basic) $ 0.22 $ 0.18 $ 0.26 $ 0.26 $ 0.92 Net income per Operating Partnership unit (diluted) $ 0.22 $ 0.18 $ 0.26 $ 0.26 $ 0.92 2017 Revenues $ 183,899 $ 184,456 $ 182,798 $ 214,542 $ 765,695 Net income 46,692 43,875 43,700 31,723 165,990 Net income per Operating Partnership unit (basic) $ 0.19 $ 0.18 $ 0.18 $ 0.12 $ 0.67 Net income per Operating Partnership unit (diluted) $ 0.19 $ 0.18 $ 0.18 $ 0.12 $ 0.66

Business - Narrative (Details)

Business - Narrative (Details) - USD ($) $ in Thousands	Jan. 29, 2019	Dec. 20, 2018	May 28, 2018	Apr. 25, 2016	Apr. 24, 2016	Sep. 30, 2019	Dec. 31, 2018	Dec. 31, 2017
Business And Organization [Line Items]
Ownership interest transferred							100.00%
Assumption of bridge facilities from Parent					$ 4,000,000
Ownership percentage acquired ( as a percent )						32.30%
Rent payments percentage							90.00%
Empire City Casino
Business And Organization [Line Items]
Assumption of bridge facilities from Parent			$ 246,000
Consideration transferred	$ 634,400		634,000
Increase In annual rent received			$ 50,000
Rent payments percentage	90.00%
Rent payment (percent)	2.00%
Units of Partnership Interest	12.9 million
Exchange of Operating Partnership Units to MGP's Class A Shares
Business And Organization [Line Items]
Operating Partnership unit conversion ratio						0.01	1
MGM
Business And Organization [Line Items]
Ownership interest in operating partnership				73.30%
Ownership percentage required for voting rights				30.00%
Operating Partnership units held (in shares)						199,700,000	195,100,000
Increase in ownership interest in operating partnership ( as a percent )						67.70%
IPO
Business And Organization [Line Items]
Shares issued under initial public offering (in shares)				57,500,000
Ownership percentage acquired ( as a percent )				26.70%
MGP Operating Partnership
Business And Organization [Line Items]
Assumption of bridge facilities from Parent					$ 4,000,000
Operating Partnership units outstanding (in shares)						295,170,610	266,045,289	266,030,918
Park MGM Lease Transaction
Business And Organization [Line Items]
Increase In annual rent received		$ 50,000
Rent payments percentage		90.00%
Rent payment (percent)		2.00%
Commitment for renovations		$ 637,500

Basis of Presentation and Sum_4

Basis of Presentation and Summary of Significant Accounting Policies - Narrative (Details)	3 Months Ended		8 Months Ended	9 Months Ended		12 Months Ended
	Sep. 30, 2019USD ($)	Sep. 30, 2018	Dec. 31, 2016USD ($)	Sep. 30, 2019USD ($)extension	Sep. 30, 2018	Dec. 31, 2018USD ($)	Dec. 31, 2018USD ($)	Dec. 31, 2018USD ($)	Dec. 31, 2018USD ($)term	Dec. 31, 2018USD ($)extension	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)	Jan. 01, 2019USD ($)	Oct. 05, 2017
Summary Of Significant Accounting Policies [Line Items]
Treasury yield term				10 years		10 years
Percentage points used in calculation for additional rent ( as a percent )				6.00%				6.00%
Non-normal tenant improvements	$ 48,400,000			$ 48,400,000		$ 144,700,000	$ 144,700,000	$ 144,700,000	$ 144,700,000	$ 144,700,000
Impairment charges							0				$ 0	$ 0
Number of lease extension options				4					4	4
Goodwill impairment loss							0
Effective tax rate	2.80%	4.50%		3.00%	3.10%			2.60%			2.90%	6.00%
Operating lease right-of-use assets	$ 280,020,000			$ 280,020,000		0	0	$ 0	$ 0	$ 0			$ 279,900,000
Operating lease liabilities	$ 336,452,000			$ 336,452,000		$ 0	$ 0	$ 0	$ 0	$ 0			$ 333,500,000
Master Lease
Summary Of Significant Accounting Policies [Line Items]
Initial lease term ( In years )	10 years			10 years		10 years	10 years	10 years	10 years	10 years				10 years
Additional extension period under Master Lease	5 years			5 years		5 years	5 years	5 years	5 years	5 years
Corporate Services Agreement
Summary Of Significant Accounting Policies [Line Items]
Expenses incurred			$ 900,000				$ 1,900,000				$ 1,600,000
Tenant
Summary Of Significant Accounting Policies [Line Items]
Initial cap of non-normal tenant improvements in the first year				$ 100,000,000			100,000,000
Annual increase in non-normal tenant improvements				$ 75,000,000			75,000,000
Operating Partnership Units to MGP's Class A Shares
Summary Of Significant Accounting Policies [Line Items]
Operating Partnership unit conversion ratio (in units)				0.01				1
MGP Operating Partnership
Summary Of Significant Accounting Policies [Line Items]
Operating lease right-of-use assets	$ 280,020,000			$ 280,020,000		$ 0	0	$ 0	$ 0	$ 0
Operating lease liabilities	336,452,000			336,452,000		0	0	0	0	0
MGP Operating Partnership | Landlord
Summary Of Significant Accounting Policies [Line Items]
Maximum exposure to loss, assets	11,800,000,000			11,800,000,000		9,800,000,000	9,800,000,000	9,800,000,000	9,800,000,000	9,800,000,000
Maximum exposure to loss, liabilities	$ 462,500,000			$ 462,500,000		$ 247,500,000	$ 247,500,000	$ 247,500,000	$ 247,500,000	$ 247,500,000

Basis of Presentation and Sum_5

Basis of Presentation and Summary of Significant Accounting Policies - Estimated Useful Lives of Leased Real Estate and Leasehold Improvements (Detail)	12 Months Ended
	Dec. 31, 2018
Buildings and building improvements | Minimum
Property Subject to or Available for Operating Lease [Line Items]
Estimated useful life	20 years
Buildings and building improvements | Maximum
Property Subject to or Available for Operating Lease [Line Items]
Estimated useful life	40 years
Land improvements | Minimum
Property Subject to or Available for Operating Lease [Line Items]
Estimated useful life	10 years
Land improvements | Maximum
Property Subject to or Available for Operating Lease [Line Items]
Estimated useful life	20 years
Furniture, fixtures and equipment | Minimum
Property Subject to or Available for Operating Lease [Line Items]
Estimated useful life	3 years
Furniture, fixtures and equipment | Maximum
Property Subject to or Available for Operating Lease [Line Items]
Estimated useful life	20 years

Acquisitions (Detail)

Acquisitions (Detail) $ in Thousands, shares in Millions	Apr. 01, 2019USD ($)	Sep. 18, 2018USD ($)	Jul. 06, 2018USD ($)	Oct. 05, 2017USD ($)ashares	Aug. 01, 2016USD ($)shares	Sep. 30, 2019USD ($)	Sep. 30, 2018USD ($)	Dec. 31, 2018USD ($)	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)	Apr. 01, 2018USD ($)
Business Acquisition
Proceeds from issuance of debt						$ 750,000	$ 0	$ 0	$ 350,000	$ 3,700,000
Operating Lease Rent Payments percentage								90.00%
Basis spread on variable rate		2.00%
Indebtedness assumed in acquisition					$ 545,000
Cash consideration								$ 0	$ 462,500	$ 0
Rent payments due under Master Lease				$ 756,700				770,300
Master Lease - Base Rent
Business Acquisition
Rent payments due under Master Lease					585,000						$ 695,800
Master Lease - Percentage Rent
Business Acquisition
Rent payments due under Master Lease					65,000
MGM National Harbor | Master Lease - Rent Increase
Business Acquisition
Rental revenues under Master Lease				95,000
Rent payments due under Master Lease				682,200
MGM National Harbor | Master Lease - Base Rent Increase
Business Acquisition
Rental revenues under Master Lease				85,500
MGM National Harbor | Master Lease - Percentage Rent Increase
Business Acquisition
Rental revenues under Master Lease				9,500
MGM National Harbor | Master Lease - Percentage Rent
Business Acquisition
Rent payments due under Master Lease				74,500
Borgata | Master Lease - Rent Increase
Business Acquisition
Rental revenues under Master Lease					100,000
Borgata | Master Lease - Base Rent Increase
Business Acquisition
Rental revenues under Master Lease					90,000
Borgata | Master Lease - Percentage Rent Increase
Business Acquisition
Rental revenues under Master Lease					10,000
Borgata | Master Lease - Percentage Rent
Business Acquisition
Rent payments due under Master Lease					$ 65,000
MGM National Harbor Transaction
Business Acquisition
Consideration transferred				1,180,000
Indebtedness assumed in acquisition				425,000
Cash consideration				$ 462,500
Operating Partnership units issued | shares				9.8
Area of land leased | a				23
Borgata Transaction
Business Acquisition
Operating Partnership units issued | shares					27.4
Northfield Park Associates, LLC
Business Acquisition
Consideration transferred	$ 305,200		$ 1,100,000
Property and equipment used in operations								792,807
Cash and cash equivalents								35,831
Racing and gaming licenses								228,000
Customer list								25,000
Goodwill								17,915
Other assets								9,598
Other liabilities								(38,786)
Assets Acquired Net								1,070,365
Revenue of Acquiree								132,900
Operating Income Of Acquiree								$ 33,000
Northfield Real Estate Leased Assets
Business Acquisition
Increase In Annual Rent Paid		$ 60,000
Senior Credit Facility Term Loan A | Secured Debt
Business Acquisition
Proceeds from issuance of debt			200,000
Senior secured revolving credit facility | Revolving Credit Facility
Business Acquisition
Proceeds from issuance of debt			$ 655,000

Acquisitions and dispositions_2

Acquisitions and dispositions - Narrative (Details) - USD ($) $ in Millions	Apr. 01, 2019	Jan. 29, 2019	Jul. 06, 2018	May 28, 2018
Business Acquisition [Line Items]
Reduction to additional paid in capital		$ 9.4
Empire City
Business Acquisition [Line Items]
Liabilities incurred		$ 246
Partnership Interest ( in units )		12,900,000
Carryover value		$ 625
Purchase price		$ 634.4		$ 634
Northfield
Business Acquisition [Line Items]
Reduction to additional paid in capital	$ 9.4
Carryover value	292.3
Membership interest acquired ( as a percent )			100.00%
Purchase price	$ 305.2		$ 1,100

Acquisitions and dispositions_3

Acquisitions and dispositions - Assets held-for-sale (Details) - Held-for-sale - Northfield OpCo $ in Thousands	Dec. 31, 2018USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Property and equipment, used in operations, net	$ 20,391
Cash and cash equivalents	55,822
Tenant and other receivables, net	7,322
Prepaid expenses and other assets	3,024
Goodwill	17,915
Other intangible assets, net	251,214
Assets held for sale	355,688
Due to MGM Resorts International and affiliates	80
Accounts payable, accrued expenses and other liabilities	28,806
Deferred revenue	51
Liabilities related to assets held for sale	$ 28,937

Acquisitions and dispositions_4

Acquisitions and dispositions - Results of discontinued operations (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended		12 Months Ended
	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Business Combinations [Abstract]
Total revenues	$ 65,562	$ 67,841	$ 65,562	$ 132,949
Total expenses	(48,997)	(48,735)	(48,997)	(97,330)
Income from discontinued operations before income taxes	16,565	19,106	16,565	35,619
Provision for income taxes	(2,616)	(2,890)	(2,616)	(5,056)
Income from discontinued operations, net of tax	13,949	16,216	13,949	30,563	$ 0	$ 0
Less: Income attributable to noncontrolling interests - discontinued operations	(10,231)	(11,434)	(10,231)	(22,417)
Income from discontinued operations attributable to Class A shareholders	$ 3,718	$ 4,782	$ 3,718	$ 8,146

Real Estate Investments (Detail

Real Estate Investments (Detail) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018	Dec. 31, 2017
Real Estate Properties [Line Items]
Real estate investments, gross	$ 13,912,939	$ 13,318,334	$ 12,655,847
Less: Accumulated depreciation	(3,018,818)	(2,812,205)	(2,633,909)
Real estate investments, net	10,894,121	10,506,129	10,021,938
Land
Real Estate Properties [Line Items]
Real estate investments, gross	4,631,013	4,536,013	4,143,513
Buildings, building improvements, land improvements and integral equipment
Real Estate Properties [Line Items]
Real estate investments, gross	$ 9,281,926	$ 8,782,321	$ 8,512,334

Leases - Narrative (Details)

Leases - Narrative (Details) $ in Thousands

Apr. 01, 2019USD ($)

Mar. 07, 2019USD ($)

Jan. 29, 2019USD ($)

Jul. 06, 2018USD ($)

May 28, 2018USD ($)

Oct. 05, 2017USD ($)

Aug. 01, 2016USD ($)

Sep. 30, 2019USD ($)

Sep. 30, 2018USD ($)

Sep. 30, 2019USD ($)extension

Sep. 30, 2018USD ($)

Dec. 31, 2018USD ($)

Dec. 31, 2018USD ($)

Dec. 31, 2018USD ($)

Dec. 31, 2018USD ($)term

Dec. 31, 2018USD ($)extension

Dec. 31, 2018USD ($)period

Dec. 31, 2017USD ($)

Dec. 31, 2016USD ($)

Apr. 02, 2019USD ($)

Mar. 30, 2019USD ($)

Sep. 18, 2018

Apr. 01, 2018USD ($)

Leases [Line Items]

Number of lease extension options

4

4

4

Rent payments due under Master Lease

$ 756,700

$ 770,300

$ 770,300

$ 770,300

$ 770,300

$ 770,300

$ 770,300

Operating Lease Rent Payments percentage

90.00%

Annual contractual rent growth rate ( as a percent )

2.00%

Number of years that the percentage rent is fixed

6 years

Number of years that percentage rent is variable

5 years

Number of periods for calculation of variable rent | period

5

Rent payments due under master lease

$ 946,100

$ 770,300

Operating lease cost

$ 5,900

$ 17,900

Revenues

$ 226,011

$ 216,659

$ 655,193

$ 652,888

$ 869,495

$ 765,695

$ 467,548

Master Lease

Leases [Line Items]

Lease extension term

5 years

5 years

5 years

5 years

5 years

5 years

5 years

5 years

Initial lease term ( In years )

10 years

10 years

10 years

10 years

10 years

10 years

10 years

10 years

10 years

Operating Leases, Income Statement, Lease Revenue

$ 746,300

675,100

419,200

Revenues

$ 219,800

186,600

$ 636,600

559,700

Master Lease - Base Rent

Leases [Line Items]

Rent payments due under Master Lease

$ 585,000

$ 695,800

Annual contractual rent growth rate ( as a percent )

2.00%

2.00%

2.00%

Annual rent escalator percentage

2.00%

2.00%

2.00%

2.00%

2.00%

2.00%

Rent payments fixed rate (as a percent)

90.00%

90.00%

90.00%

Percentage Rent

Leases [Line Items]

Rent payments due under Master Lease

65,000

Percentage of initial total rent payments due under the master lease

10.00%

Lease fixed amount adjustment multiplier

1.40%

Tenant Reimbursements

Leases [Line Items]

Operating Leases, Income Statement, Lease Revenue

$ 123,242

$ 90,606

48,309

Revenues

$ 6,164

$ 30,095

$ 18,618

$ 93,198

$ 48,309

MGM National Harbor | Percentage Rent

Leases [Line Items]

Rent payments due under Master Lease

$ 74,500

MGM National Harbor | Rent Increase

Leases [Line Items]

Rent payments due under Master Lease

682,200

Rental revenues under Master Lease

95,000

MGM National Harbor | Base Rent Increase

Leases [Line Items]

Rental revenues under Master Lease

85,500

MGM National Harbor | Percentage Rent Increase

Leases [Line Items]

Rental revenues under Master Lease

$ 9,500

Borgata | Master Lease

Leases [Line Items]

Rental revenues under Master Lease

550,000

Borgata | Percentage Rent

Leases [Line Items]

Rent payments due under Master Lease

65,000

Borgata | Rent Increase

Leases [Line Items]

Rental revenues under Master Lease

100,000

Borgata | Base Rent Increase

Leases [Line Items]

Rental revenues under Master Lease

90,000

Borgata | Percentage Rent Increase

Leases [Line Items]

Rental revenues under Master Lease

$ 10,000

Park MGM Lease Transaction

Leases [Line Items]

Business Acquisition, Transaction Costs

$ 637,500

Business Combination, Consideration Transferred, Other

605,600

Rent payments due under master lease

50,000

Park MGM Lease Transaction | Operating Partnership Units [Member]

Leases [Line Items]

Operating partnership units

1,000

Park MGM Lease Transaction | Tenant Reimbursements

Leases [Line Items]

Operating Leases, Income Statement, Lease Revenue

$ 94,000

Empire City

Leases [Line Items]

Operating Lease Rent Payments percentage

90.00%

Business Acquisition, Transaction Costs

$ 634,400

$ 634,000

Rent payments due under master lease

$ 50,000

Rent payments fixed rate (as a percent)

2.00%

Northfield Op Co [Member]

Leases [Line Items]

Rent payments due under master lease

$ 60,000

Northfield

Leases [Line Items]

Business Acquisition, Transaction Costs

305,200

$ 1,100,000

Rent payments due under master lease

$ 60,000

Leases - Future Noncancelable M

Leases - Future Noncancelable Minimum Rental Payments (Detail) $ in Thousands	Dec. 31, 2018USD ($)
2019	$ 780,782
2020	794,907
2021	809,315
2022	757,060
2023	738,435
Thereafter	1,568,769
Total	$ 5,449,268

Leases - Operating Lease Minimu

Leases - Operating Lease Minimum Rental Payments (Details) $ in Thousands	Sep. 30, 2019USD ($)
Leases [Abstract]
2019	$ 236,515
2020	958,894
2021	976,262
2022	912,751
2023	890,126
Thereafter	1,922,713
Total	$ 5,897,261

Leases - Lease Cost (Details)

Leases - Lease Cost (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2019	Jan. 01, 2019	Dec. 31, 2018
Leases [Abstract]
Operating lease right-of-use assets	$ 280,020
Operating lease liabilities	$ 336,452	$ 333,500	$ 0
Weighted-average remaining lease term (years)	59 years
Weighted-average discount rate (%)	7.00%

Leases - Operating Lease Maturi

Leases - Operating Lease Maturities (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Jan. 01, 2019	Dec. 31, 2018
Leases [Abstract]
2019 (excluding the nine months ended September 30, 2019)	$ 4,541
2020	21,113
2021	24,996
2022	25,015
2023	24,875
Thereafter	1,357,650
Total future minimum lease payments	1,458,190
Less: Amount of lease payments representing interest	(1,121,738)
Operating lease liabilities	$ 336,452	$ 333,500	$ 0

Debt (Detail)

Debt (Detail) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Total	$ 4,902,313	$ 4,719,125	$ 3,991,375
Less: Unamortized discount and debt issuance costs	(54,905)	(52,176)	(56,747)
Long-term debt, net	4,847,408	4,666,949	3,934,628
Senior secured term loan A facility | Term Loan
Debt Instrument [Line Items]
Senior secured term loan	467,063	470,000	273,750
Principal amount	$ 467,000	470,000
Interest rate	4.04%
Senior secured term loan B facility | Term Loan
Debt Instrument [Line Items]
Senior secured term loan	$ 1,785,250	1,799,125	1,817,625
Principal amount	1,800,000	1,800,000
Senior secured revolving credit facility | Revolving Credit Facility
Debt Instrument [Line Items]
Credit facility	0	550,000	0
5.625% Senior Notes Due 2024 | Senior Notes
Debt Instrument [Line Items]
Senior notes	1,050,000	1,050,000	1,050,000
Principal amount	$ 1,050,000	$ 1,050,000	$ 1,050,000
Interest rate	5.625%	5.625%	5.625%
4.50% senior notes, due 2026 | Senior Notes
Debt Instrument [Line Items]
Senior notes	$ 500,000	$ 500,000	$ 500,000
Principal amount	$ 500,000	$ 500,000	$ 500,000
Interest rate	4.50%	4.50%	4.50%
5.75% senior notes due 2027 | Senior Notes
Debt Instrument [Line Items]
Senior notes	$ 750,000	$ 0
Principal amount	$ 750,000
Interest rate	5.75%
4.50% senior notes, due 2028 | Senior Notes
Debt Instrument [Line Items]
Senior notes	$ 350,000	350,000	$ 350,000
Principal amount	$ 350,000	$ 350,000	$ 350,000
Interest rate	4.50%	4.50%	4.50%

Debt - Operating Partnership Cr

Debt - Operating Partnership Credit Agreement (Detail) - USD ($) $ in Thousands	1 Months Ended		3 Months Ended	12 Months Ended
	Jun. 30, 2018	Mar. 31, 2018	Mar. 31, 2018	Dec. 31, 2018	Sep. 30, 2019	Dec. 31, 2017
Operating Partnership Credit Agreement | Senior secured term loan A facility
Debt Instrument [Line Items]
Term loan repayment percentage of initial aggregate principal amount				2.50%
Repayments of Debt				$ 3,800
Interest rate				4.52%
Operating Partnership Credit Agreement | Senior secured term loan B facility
Debt Instrument [Line Items]
Term loan repayment percentage of initial aggregate principal amount				1.00%
Repayments of Debt				$ 18,500
Interest rate				4.52%
Operating Partnership Credit Agreement | Senior secured revolving credit facility
Debt Instrument [Line Items]
Interest rate				4.43%
Secured Debt | Senior secured term loan A facility
Debt Instrument [Line Items]
Principal amount				$ 470,000	$ 467,000
Credit facility amount	$ 200,000
Debt Instrument, Payment Terms, Percent Of Principal Due At Payment	0.625%
Interest rate					4.04%
Secured Debt | Senior secured term loan A facility | LIBOR
Debt Instrument [Line Items]
Variable margin	2.25%
Secured Debt | Senior secured term loan B facility
Debt Instrument [Line Items]
Principal amount				1,800,000	$ 1,800,000
Secured Debt | Senior secured term loan B facility | LIBOR
Debt Instrument [Line Items]
Variable margin			2.00%
Debt Instrument, Basis Spread On Variable Rate Upon Rating Upgrade		1.75%
Revolving Credit Facility | Senior secured revolving credit facility
Debt Instrument [Line Items]
Credit facility amount	$ 1,400,000				1,400,000
Variable margin	1.75%
Line Of Credit Facility, Increase (Decrease) In Maximum Borrowing Capacity	$ 750,000
Amounts drawn on credit facility				$ 550,000	$ 0	$ 0

Debt - Operating Partnership Se

Debt - Operating Partnership Senior Notes (Detail) - Operating Partnership Senior Notes - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Jan. 31, 2019	Sep. 30, 2017	Aug. 31, 2016	Apr. 30, 2016
$1,050 million 5.625% senior notes, due 2024
Debt Instrument [Line Items]
Aggregate principal amount					$ 1,050
Interest rate					5.625%
Debt instrument redemption price percentage	100.00%
$500 million 4.50% senior notes, due 2026
Debt Instrument [Line Items]
Aggregate principal amount				$ 500
Interest rate				4.50%
Debt instrument redemption price percentage	100.00%
$350 million 4.50% senior notes, due 2028
Debt Instrument [Line Items]
Aggregate principal amount			$ 350
Interest rate		5.75%	4.50%
Debt instrument redemption price percentage	100.00%
$750 million 5.75% senior notes due 2027
Debt Instrument [Line Items]
Aggregate principal amount		$ 750
Interest rate		5.75%

Debt - Maturities of the Princi

Debt - Maturities of the Principal Amount of Debt (Detail) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018	Dec. 31, 2017
2019		$ 24,375
2020		30,250
2021		30,250
2022		30,250
2023		997,375
Thereafter		3,606,625
Total	$ 4,902,313	$ 4,719,125	$ 3,991,375

Debt - Fair value of long-term

Debt - Fair value of long-term debt (Detail) - USD ($) $ in Billions	Sep. 30, 2019	Dec. 31, 2018	Dec. 31, 2017
Estimated fair value of long-term debt	$ 5.1	$ 4.5	$ 4.1

Debt - Deferred financing costs

Debt - Deferred financing costs (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Amortization of deferred financing costs	$ 3.2	$ 3.3	$ 9.6	$ 9.4	$ 12	$ 11.4	$ 7.2

Debt - Narrative (Details)

Debt - Narrative (Details) - USD ($) $ in Thousands	Jan. 29, 2019	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Jan. 31, 2019	Jun. 30, 2018
Debt Instrument [Line Items]
Estimated fair value of long-term debt		$ 5,100,000		$ 5,100,000		$ 4,500,000	$ 4,100,000
Amortization of deferred financing costs		3,200	$ 3,300	9,600	$ 9,400	12,000	11,400	$ 7,200
Empire City Casino
Debt Instrument [Line Items]
Liabilities incurred	$ 246,000
Term Loan | Senior secured term loan A facility
Debt Instrument [Line Items]
Principal amount under term loan facility		$ 467,000		$ 467,000		470,000
Borrowing capacity under credit facility										$ 200,000
Interest rate		4.04%		4.04%
Term Loan | Senior secured term loan B facility
Debt Instrument [Line Items]
Principal amount under term loan facility		$ 1,800,000		$ 1,800,000		1,800,000
Revolving Credit Facility | Senior secured revolving credit facility
Debt Instrument [Line Items]
Borrowing capacity under credit facility		1,400,000		1,400,000						$ 1,400,000
Amounts drawn on credit facility		$ 0		$ 0		$ 550,000	$ 0
Operating Partnership Senior Notes | 5.75% senior notes due 2027
Debt Instrument [Line Items]
Interest rate									5.75%
Senior notes									$ 750,000

Derivatives and Hedging Activ_3

Derivatives and Hedging Activities - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Derivative [Line Items]
Derivative liability	$ (54,570)		$ (54,570)
Gain on derivative instrument	$ (19,270)	$ 4,736	$ (65,657)	$ 27,372	$ 4,128	$ 9,782	$ 1,879
Interest rate swaps
Derivative [Line Items]
Weighted average fixed rate ( as a percent )	1.707%		1.707%		1.844%	1.844%
Notional amount	$ 1,500,000		$ 1,500,000		$ 1,200,000	$ 1,200,000
LIBOR floor rate					0.00%
Gain on derivative instrument					$ 4,100	9,800
Interest Income (Expense), Net					1,100	9,200
Interest rate swaps | Prepaid Expenses and Other Assets [Member]
Derivative [Line Items]
Derivative Asset Fair Value					20,500	11,300
Interest rate swaps | Designated as Hedging Instrument
Derivative [Line Items]
Notional amount					400,000
Derivative liability	54,600		54,600		5,600	$ 0
Fair value of derivative instruments	$ 3,400		$ 3,400		$ 20,500
Fixed Interest Rate					2.735%
September 6, 2019
Derivative [Line Items]
Weighted average fixed rate ( as a percent )	1.158%		1.158%
Notional amount	$ 300,000		$ 300,000
Fair value of derivative instruments	3,393		3,393
May 3, 2017
Derivative [Line Items]
Derivative liability	$ (9,926)		$ (9,926)
October 1, 2019
Derivative [Line Items]
Weighted average fixed rate ( as a percent )	2.252%		2.252%
Notional amount	$ 400,000		$ 400,000
Derivative liability	$ (31,370)		$ (31,370)
November 30, 2021
Derivative [Line Items]
Weighted average fixed rate ( as a percent )	1.801%		1.801%
Notional amount	$ 900,000		$ 900,000
Derivative liability	$ (13,274)		$ (13,274)

Derivatives and Hedging Activ_4

Derivatives and Hedging Activities - Schedule of Interest Rate Derivatives (Details) $ in Thousands	Sep. 30, 2019USD ($)
Derivative [Line Items]
Derivative liability	$ (54,570)

Income Taxes - Narrative (Detai

Income Taxes - Narrative (Detail) - USD ($)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Real Estate [Line Items]
Minimum percentage of taxable income distributed to shareholders					90.00%
Expected distribution percentage of REIT taxable income in the current taxable year					100.00%
Income tax expense	$ 1,979,000	$ 2,650,000	$ 5,771,000	$ 5,144,000	$ 5,779,000	$ 4,906,000	$ 2,264,000
Amounts due to MGM under tax sharing agreement					0	0
Uncertain tax positions					0
Interest and penalties recorded					$ 0	$ 0
Income tax rate					21.00%	35.00%	35.00%
Taxable REIT subsidiaries
Real Estate [Line Items]
Income tax expense					$ 3,900,000
Taxable REIT subsidiaries | Continuing Operations [Member]
Real Estate [Line Items]
Income tax expense					1,200,000
Taxable REIT subsidiaries | Discontinued Operations [Member]
Real Estate [Line Items]
Income tax expense					$ 5,100,000

Income Taxes - Provision for In

Income Taxes - Provision for Income Taxes Attributable to Income (Loss) Before Income Taxes (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Federal:
Current	$ 0	$ 0	$ 0
Deferred	(1,142)	0	0
Provision for federal income taxes	(1,142)	0	0
State:
Current	5,746	1,729	2,156
Deferred	1,175	3,177	108
Provision for state income taxes	$ 6,921	$ 4,906	$ 2,264

Income Taxes - Reconciliation o

Income Taxes - Reconciliation of Federal Income Tax Statutory Rate and Effective Tax Rate (Detail)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Real Estate [Line Items]
Federal income tax statutory rate					21.00%	35.00%	35.00%
Federal valuation allowance					0.00%	0.00%	0.00%
Income not subject to federal income tax					(21.50%)	(35.00%)	(35.00%)
State taxes					3.10%	2.90%	6.00%
Effective tax rate	2.80%	4.50%	3.00%	3.10%	2.60%	2.90%	6.00%

Income Taxes - Major Tax-Effect

Income Taxes - Major Tax-Effected Components of Net Deferred Tax Liability (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Deferred tax asset — federal and state
Accruals, reserves and other	$ 1,844	$ 0
Total deferred tax asset	1,844	0
Deferred tax liability — federal and state
Real estate investments, net	(33,466)	(28,544)
Other intangible assets, net	(2,012)	0
Total deferred tax liability	(35,478)	(28,544)
Net deferred tax liability	$ (33,634)	$ (28,544)

Shareholders' Equity and Part_3

Shareholders' Equity and Partners' Capital - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions	Oct. 15, 2019	Apr. 01, 2019	Mar. 07, 2019	Jan. 31, 2019	Sep. 11, 2017	Sep. 30, 2019	Sep. 30, 2019	Dec. 31, 2018	Dec. 31, 2017	Apr. 30, 2019	Apr. 02, 2019	Mar. 06, 2019	Jan. 30, 2019	Jan. 29, 2019	Jan. 28, 2019	Oct. 05, 2017
Class A Shares
Dividend Declared								$ 1.7075	$ 1.5297
Dividends Declared, Ordinary								1.2669	1.1542
Non-Dividend Distribution								$ 0.4406	$ 0.3755
Common Stock										$ 300
Subsidiaries
Partnership Interest ( in units )																9,800,000
Empire City Casino
Partnership Interest ( in units )														12,900,000
Ownership percentage														25.40%	26.70%
Park MGM Lease Transaction
Ownership percentage			30.20%									30.30%
Northfield
Ownership percentage		30.20%				32.30%	32.30%				31.20%
Subsequent Event | Class A Shares
Dividends	$ 0.4700
Dividends	$ 0.4700
Subsequent Event | Empire City Casino
Partnership Interest ( in units )														12,900,000
Public Stock Offering | Class A Shares
Number of shares offered in public offering (in shares)				19,600,000	13,200,000	2,800,000
Net proceeds from public offering of stock				$ 548.4	$ 387.5	$ 86.1	$ 151
Ownership percentage				30.30%									25.40%
Public Stock Offering | Subsequent Event | Class A Shares
Number of shares offered in public offering (in shares)				19,600,000
Net proceeds from public offering of stock				$ 548.4
Over-Allotment Option | Class A Shares
Number of shares offered in public offering (in shares)				2,600,000	1,700,000
Net proceeds from public offering of stock							$ 4.9
Over-Allotment Option | Subsequent Event | Class A Shares
Number of shares offered in public offering (in shares)				2,600,000
Operating Partnership Units
Operating partnership units						2,800,000	4,900,000
Operating Partnership Units | Park MGM Lease Transaction
Operating partnership units			1,000,000
Operating Partnership Units | Northfield
Operating partnership units		9,400,000

Shareholders' Equity and Part_4

Shareholders' Equity and Partners' Capital - Changes in Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended			12 Months Ended
	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
AOCI [Roll Forward]
Balance	$ 6,386,532	$ 6,716,917	$ 5,845,506	$ 6,067,739	$ 5,608,261	$ 6,058,959
Balance	6,384,304	6,386,532	6,716,917	5,845,506	6,067,739	5,608,261
AOCI Attributable to Parent
AOCI [Roll Forward]
Balance	(9,696)	54	4,208	3,108	445	0
Balance	(16,129)	(9,696)	54	4,208	3,108	445
Accumulated Net Gain (Loss) from Cash Flow Hedges Including Portion Attributable to Noncontrolling Interest
AOCI [Roll Forward]
Other comprehensive income (loss) before reclassifications				5,258	566
Amounts reclassified from accumulated other comprehensive income to interest expense				(1,130)	9,216
Less: Other comprehensive (income) loss attributable to noncontrolling interest				4,128	9,782
AOCI Attributable to Noncontrolling Interest
AOCI [Roll Forward]
Less: Other comprehensive (income) loss attributable to noncontrolling interest				(3,028)	(7,119)
MGP Operating Partnership
AOCI [Roll Forward]
Acquisitions					296,409	728,379
MGP Operating Partnership | Limited Partners
AOCI [Roll Forward]
Acquisitions					$ 296,409	$ 728,379
Empire City Casino | MGP Operating Partnership
AOCI [Roll Forward]
Acquisitions			379,050
Empire City Casino | MGP Operating Partnership | Limited Partners
AOCI [Roll Forward]
Acquisitions			379,050
Park MGM Lease Transaction | MGP Operating Partnership
AOCI [Roll Forward]
Acquisitions			31,875
Park MGM Lease Transaction | MGP Operating Partnership | Limited Partners
AOCI [Roll Forward]
Acquisitions			31,875
Other Comprehensive Income (Loss)
AOCI [Roll Forward]
Balance	(9,696)	54	4,208
Other comprehensive income (loss) before reclassifications	(17,989)	(29,008)	(13,765)
Amounts reclassified from accumulated other comprehensive income to interest expense	(1,281)	(1,767)	(1,847)
Less: Other comprehensive (income) loss attributable to noncontrolling interest	(19,470)	(30,878)	(15,049)
Balance	(16,129)	(9,696)	54	4,208
Other Comprehensive Income (Loss) | AOCI Attributable to Parent
AOCI [Roll Forward]
Balance	(10,156)	(509)	4,208
Balance	(16,389)	(10,156)	(509)	4,208
Other Comprehensive Income (Loss) | Accumulated Net Gain (Loss) from Cash Flow Hedges Including Portion Attributable to Noncontrolling Interest
AOCI [Roll Forward]
Other comprehensive income (loss) before reclassifications	(17,989)	(29,008)	(13,765)
Amounts reclassified from accumulated other comprehensive income to interest expense	(1,281)	(1,767)	(1,847)
Less: Other comprehensive (income) loss attributable to noncontrolling interest	(19,270)	(30,775)	(15,612)
Other Comprehensive Income (Loss) | AOCI Attributable to Noncontrolling Interest
AOCI [Roll Forward]
Less: Other comprehensive (income) loss attributable to noncontrolling interest	13,037	21,128	10,895
Other Comprehensive Income (Loss) | Limited Partners
AOCI [Roll Forward]
Balance	460	563	0
Less: Other comprehensive (income) loss attributable to noncontrolling interest	(200)	(103)	563
Balance	260	460	563	$ 0
Other Comprehensive Income (Loss) | MGP Operating Partnership
AOCI [Roll Forward]
Issuance of Operating Partnership units	(200)	(105)	774
Other Comprehensive Income (Loss) | MGP Operating Partnership | Northfield Op Co [Member]
AOCI [Roll Forward]
Acquisitions		2
Other Comprehensive Income (Loss) | MGP Operating Partnership | Limited Partners
AOCI [Roll Forward]
Issuance of Operating Partnership units	$ (200)	(105)	774
Other Comprehensive Income (Loss) | MGP Operating Partnership | Limited Partners | Northfield Op Co [Member]
AOCI [Roll Forward]
Acquisitions		$ 2
Other Comprehensive Income (Loss) | Empire City Casino | MGP Operating Partnership
AOCI [Roll Forward]
Acquisitions			(195)
Other Comprehensive Income (Loss) | Empire City Casino | MGP Operating Partnership | Limited Partners
AOCI [Roll Forward]
Acquisitions			(195)
Other Comprehensive Income (Loss) | Park MGM Lease Transaction | MGP Operating Partnership
AOCI [Roll Forward]
Acquisitions			(16)
Other Comprehensive Income (Loss) | Park MGM Lease Transaction | MGP Operating Partnership | Limited Partners
AOCI [Roll Forward]
Acquisitions			$ (16)

Net Income Per Class A Share _2

Net Income Per Class A Share - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended									8 Months Ended	9 Months Ended		12 Months Ended
	Sep. 30, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Numerator:
Income from continuing operations	$ 68,553		$ 55,974							$ 35,346	$ 186,470	$ 162,202	$ 214,139	$ 165,990	$ 35,346
Income from continuing operations attributable to noncontrolling interest	(46,038)		(40,208)							(5,408)	(126,924)	(117,460)	(155,220)	(124,215)	(35,346)
Income from continuing operations attributable to Class A shares - basic and diluted	22,515		15,766							29,938	59,546	44,742	58,919	41,775
Income from discontinued operations	0		13,949								16,216	13,949	30,563	0	0
Income from discontinued operations attributable to noncontrolling interest			(10,231)								(11,434)	(10,231)	(22,417)
Income from discontinued operations attributable to Class A shares - basic and diluted			3,718								4,782	3,718	8,146
Net income attributable to Class A shares - basic and diluted	$ 22,515	$ 18,605	$ 19,484	$ 13,146	$ 15,830	$ 8,722	$ 11,025	$ 10,680	$ 11,348	$ 29,938	$ 64,328	$ 48,460	$ 67,065	$ 41,775	$ 29,938
Denominator:
Basic weighted average Class A shares outstanding (in shares)	93,165,443		71,005,052							57,502,158	89,440,552	70,991,129	70,997,589	61,733,136	57,502,158
Effect of dilutive shares for diluted net income per Class A share (in shares)	157,497		196,739							249,331	204,557	183,141	188,085	183,410
Weighted average shares for diluted net income per Class A share (in shares)	93,322,940		71,201,791							57,751,489	89,645,109	71,174,270	71,185,674	61,916,546	57,751,489

Net Income Per Operating Part_3

Net Income Per Operating Partnership Unit - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended											4 Months Ended	8 Months Ended	9 Months Ended		12 Months Ended
	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Apr. 24, 2016	Dec. 31, 2016	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Numerator:
Income from continuing operations	$ 68,553				$ 55,974								$ 35,346	$ 186,470	$ 162,202	$ 214,139	$ 165,990	$ 35,346
Income from discontinued operations	0				13,949									16,216	13,949	30,563	0	0
Net income - basic and diluted	$ 68,553	$ 67,769	$ 66,364	$ 68,551	$ 69,923	$ 48,059	$ 58,169	$ 31,723	$ 43,700	$ 43,875	$ 46,692	$ (84,383)	$ 119,729	$ 202,686	$ 176,151	$ 244,702	$ 165,990	35,346
Denominator:
Effect of dilutive shares for diluted net income per Operating Partnership unit (in shares)	157,497				196,739								249,331	204,557	183,141	188,085	183,410
MGP Operating Partnership
Numerator:
Income from continuing operations	$ 68,553				$ 55,974								$ 119,729	$ 186,470	$ 162,202	$ 214,139	$ 165,990	35,346
Income from discontinued operations	0				13,949								0	16,216	13,949	30,563	0	0
Net income - basic and diluted	$ 68,553	$ 67,769	$ 66,364	$ 68,551	$ 69,923	$ 48,059	$ 58,169	$ 31,723	$ 43,700	$ 43,875	$ 46,692	$ (84,383)	$ 119,729	$ 202,686	$ 176,151	$ 244,702	$ 165,990	$ 35,346
Denominator:
Weighted average Operating Partnership units outstanding - basic (in shares)	292,867,986				266,139,175								232,181,070	290,661,305	266,125,252	266,131,712	249,451,258	232,181,070
Effect of dilutive shares for diluted net income per Operating Partnership unit (in shares)	157,497				196,739								249,331	204,557	183,141	188,085	183,410
Weighted average Operating Partnership units outstanding - diluted (in shares)	293,025,483				266,335,914								232,430,401	290,865,862	266,308,393	266,319,797	249,634,668	232,430,401

Commitments and Contingencies_2

Commitments and Contingencies (Detail) $ in Thousands	Dec. 31, 2018USD ($)
Commitments And Contingencies Disclosure [Line Items]
2019	$ 19,868
2020	21,113
2021	24,996
2022	25,015
2023	24,875
Thereafter	1,310,253
Total minimum lease payments	$ 1,426,120

Condensed Consolidating Finan_3

Condensed Consolidating Financial Information - Consolidating Balance Sheet Information (Detail) - USD ($) $ in Thousands	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Jan. 01, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Condensed Balance Sheet Statements, Captions [Line Items]
Real estate investments, net	$ 10,894,121				$ 10,506,129				$ 10,021,938
Lease incentive asset	532,186				0
Cash and cash equivalents	153,526				3,995	$ 8,051			259,722	$ 360,492	$ 0
Tenant and other receivables, net	463				7,668				6,385
Prepaid expenses and other assets	27,413				34,813				18,487
Above market lease, asset	41,834				43,014				44,588
Operating lease right-of-use assets	280,020			$ 279,900	0
Total assets	11,929,563				10,951,307				10,351,120
Debt, net	4,847,408				4,666,949				3,934,628
Due to MGM Resorts International and affiliates	298				227				962
Accounts payable, accrued expenses and other liabilities	59,937				20,796				10,240
Above market lease, liability	0				46,181				47,069
Accrued interest	37,407				26,096				22,565
Dividend and distribution payable	138,730				119,055				111,733
Deferred revenue	95,306				163,926				127,640
Deferred income taxes, net	29,721				33,634				28,544
Operating lease liabilities	336,452			$ 333,500	0
Total liabilities	5,545,259				5,105,801				4,283,381
Total liabilities and shareholders' equity	11,929,563				10,951,307				10,351,120
MGP Operating Partnership
Condensed Balance Sheet Statements, Captions [Line Items]
Real estate investments, net	10,894,121				10,506,129				10,021,938
Lease incentive asset	532,186				0
Cash and cash equivalents	153,526				3,995	8,051			259,722	360,492	0
Tenant and other receivables, net	463				7,668				6,385
Intercompany	0				0				0
Prepaid expenses and other assets	27,413				34,813				18,487
Investments in subsidiaries	0				0				0
Above market lease, asset	41,834				43,014				44,588
Operating lease right-of-use assets	280,020				0
Assets held for sale					355,688
Total assets	11,929,563				10,951,307				10,351,120
Debt, net	4,847,408				4,666,949				3,934,628
Due to MGM Resorts International and affiliates	298				227				962
Intercompany	0				0				0
Accounts payable, accrued expenses and other liabilities	59,937				20,796				10,240
Above market lease, liability	0				46,181				47,069
Accrued interest	37,407				26,096				22,565
Dividend and distribution payable	138,730				119,055				111,733
Deferred revenue	95,306				163,926				127,640
Deferred income taxes, net	29,721				33,634				28,544
Operating lease liabilities	336,452				0
Liabilities related to assets held for sale					28,937
Total liabilities	5,545,259				5,105,801				4,283,381
General partner	0				0				0
Limited partners	6,384,304				5,845,506				6,067,739
Total partners' capital	6,384,304	$ 6,386,532	$ 6,716,917		5,845,506	5,915,203	$ 5,974,303	$ 6,032,546	6,067,739	5,608,261	6,058,959
Total liabilities and shareholders' equity	11,929,563				10,951,307				10,351,120
MGP Operating Partnership | Eliminations
Condensed Balance Sheet Statements, Captions [Line Items]
Real estate investments, net	0				0				0
Lease incentive asset	0
Cash and cash equivalents	0				0	0			0	0	0
Tenant and other receivables, net	0				0				0
Intercompany	(1,169,999)				(841,179)				(1,383,397)
Prepaid expenses and other assets	0				0				0
Investments in subsidiaries	(10,126,379)				(9,790,350)				(8,479,388)
Above market lease, asset	0				0				0
Operating lease right-of-use assets	0
Assets held for sale					0
Total assets	(11,296,378)				(10,631,529)				(9,862,785)
Debt, net	0				0				0
Due to MGM Resorts International and affiliates	0				0				0
Intercompany	(1,169,999)				(841,179)				(1,383,397)
Accounts payable, accrued expenses and other liabilities	0				0				0
Above market lease, liability					0				0
Accrued interest	0				0				0
Dividend and distribution payable	0				0				0
Deferred revenue	0				0				0
Deferred income taxes, net	0				0				0
Operating lease liabilities	0
Liabilities related to assets held for sale					0
Total liabilities	(1,169,999)				(841,179)				(1,383,397)
General partner	0				0				0
Limited partners	(10,126,379)				(9,790,350)				(8,479,388)
Total partners' capital	(10,126,379)				(9,790,350)				(8,479,388)
Total liabilities and shareholders' equity	(11,296,378)				(10,631,529)				(9,862,785)
MGP Operating Partnership | Operating Partnership | Reportable Legal Entities
Condensed Balance Sheet Statements, Captions [Line Items]
Real estate investments, net	507				572				488
Lease incentive asset	0
Cash and cash equivalents	153,526				3,995	8,051			259,722	360,492	0
Tenant and other receivables, net	463				26				299
Intercompany	1,169,999				841,179				1,383,397
Prepaid expenses and other assets	15,730				34,813				18,487
Investments in subsidiaries	10,126,379				9,790,350				8,479,388
Above market lease, asset	0				0				0
Operating lease right-of-use assets	477
Assets held for sale					0
Total assets	11,467,081				10,670,935				10,141,781
Debt, net	4,847,408				4,666,949				3,934,628
Due to MGM Resorts International and affiliates	298				227				962
Intercompany	0				0				0
Accounts payable, accrued expenses and other liabilities	58,457				13,102				4,154
Above market lease, liability					0				0
Accrued interest	37,407				26,096				22,565
Dividend and distribution payable	138,730				119,055				111,733
Deferred revenue	0				0				0
Deferred income taxes, net	0				0				0
Operating lease liabilities	477
Liabilities related to assets held for sale					0
Total liabilities	5,082,777				4,825,429				4,074,042
General partner	0				0				0
Limited partners	6,384,304				5,845,506				6,067,739
Total partners' capital	6,384,304				5,845,506				6,067,739
Total liabilities and shareholders' equity	11,467,081				10,670,935				10,141,781
MGP Operating Partnership | Co-Issuer | Reportable Legal Entities
Condensed Balance Sheet Statements, Captions [Line Items]
Real estate investments, net	0				0				0
Lease incentive asset	0
Cash and cash equivalents	0				0	0			0	0	0
Tenant and other receivables, net	0				0				0
Intercompany	0				0				0
Prepaid expenses and other assets	0				0				0
Investments in subsidiaries	0				0				0
Above market lease, asset	0				0				0
Operating lease right-of-use assets	0
Assets held for sale					0
Total assets	0				0				0
Debt, net	0				0				0
Due to MGM Resorts International and affiliates	0				0				0
Intercompany	0				0				0
Accounts payable, accrued expenses and other liabilities	0				0				0
Above market lease, liability					0				0
Accrued interest	0				0				0
Dividend and distribution payable	0				0				0
Deferred revenue	0				0				0
Deferred income taxes, net	0				0				0
Operating lease liabilities	0
Liabilities related to assets held for sale					0
Total liabilities	0				0				0
General partner	0				0				0
Limited partners	0				0				0
Total partners' capital	0				0				0
Total liabilities and shareholders' equity	0				0				0
MGP Operating Partnership | Guarantor Subsidiaries | Reportable Legal Entities
Condensed Balance Sheet Statements, Captions [Line Items]
Real estate investments, net	10,893,614				10,505,557				10,021,450
Lease incentive asset	532,186
Cash and cash equivalents	0				0	$ 0			0	$ 0	$ 0
Tenant and other receivables, net	0				7,642				6,086
Intercompany	0				0				0
Prepaid expenses and other assets	11,683				0				0
Investments in subsidiaries	0				0				0
Above market lease, asset	41,834				43,014				44,588
Operating lease right-of-use assets	279,543
Assets held for sale					355,688
Total assets	11,758,860				10,911,901				10,072,124
Debt, net	0				0				0
Due to MGM Resorts International and affiliates	0				0				0
Intercompany	1,169,999				841,179				1,383,397
Accounts payable, accrued expenses and other liabilities	1,480				7,694				6,086
Above market lease, liability					46,181				47,069
Accrued interest	0				0				0
Dividend and distribution payable	0				0				0
Deferred revenue	95,306				163,926				127,640
Deferred income taxes, net	29,721				33,634				28,544
Operating lease liabilities	335,975
Liabilities related to assets held for sale					28,937
Total liabilities	1,632,481				1,121,551				1,592,736
General partner	0				0				0
Limited partners	10,126,379				9,790,350				8,479,388
Total partners' capital	10,126,379				9,790,350				8,479,388
Total liabilities and shareholders' equity	$ 11,758,860				$ 10,911,901				$ 10,072,124

Condensed Consolidating Finan_4

Condensed Consolidating Financial Information - Consolidating Statement of Operations and Comprehensive Income Information (Detail) - USD ($) $ in Thousands	3 Months Ended											4 Months Ended	8 Months Ended	9 Months Ended		12 Months Ended
	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Apr. 24, 2016	Dec. 31, 2016	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Condensed Income Statements, Captions [Line Items]
Revenues	$ 226,011				$ 216,659									$ 655,193	$ 652,888	$ 869,495	$ 765,695	$ 467,548
Expenses
Depreciation and amortization	71,957				63,468									223,062	199,933	266,622	260,455	220,667
Property transactions, net	9,921				339									11,344	18,851	20,319	34,022	4,684
Reimbursable expenses	5,920				29,168									17,760	90,435	119,531	88,254	68,063
Amortization of above market lease, net	0				171									0	514	686	686	286
Acquisition-related expenses	92				1,931									8,891	4,603	6,149	17,304	10,178
General and administrative	4,476				3,358									12,305	10,021	16,048	12,189	9,896
Expenses, net	92,366				98,435									273,362	324,357	429,355	412,910	313,774
Operating income (loss)																440,140	352,785	153,774
Equity in earnings of subsidiaries																		0
Non-operating income (expense)
Interest income	241				163									2,189	2,473	2,501	3,907	774
Interest expense	(63,048)				(58,743)									(190,973)	(157,249)	(215,532)	(184,175)	(116,212)
Other non-operating	(306)				(1,020)									(806)	(6,409)	(7,191)	(1,621)	(726)
Non-operating income (expense)	(63,113)				(59,600)									(189,590)	(161,185)	(220,222)	(181,889)	(116,164)
Income from continuing operations before income taxes	70,532				58,624									192,241	167,346	219,918	170,896	37,610
Provision for income taxes	(1,979)				(2,650)									(5,771)	(5,144)	(5,779)	(4,906)	(2,264)
Net income (loss)	46,038				40,208								$ 5,408	126,924	117,460	155,220	124,215	35,346
Income from discontinued operations					10,231									11,434	10,231	22,417
Other comprehensive income (loss)
Net income (loss)	68,553	$ 67,769	$ 66,364	$ 68,551	69,923	$ 48,059	$ 58,169	$ 31,723	$ 43,700	$ 43,875	$ 46,692	$ (84,383)	119,729	202,686	176,151	244,702	165,990	35,346
Unrealized gain (loss) on cash flow hedges, net	(19,270)				4,736									(65,657)	27,372	4,128	9,782	1,879
Comprehensive income (loss)	49,283				74,659									137,029	203,523	248,830	175,772	37,225
Rental revenue
Condensed Income Statements, Captions [Line Items]
Revenues	219,847				186,564									636,575	559,690	746,253	675,089	419,239
Tenant reimbursements and other
Condensed Income Statements, Captions [Line Items]
Revenues	6,164				30,095									18,618	93,198			48,309
Eliminations
Condensed Income Statements, Captions [Line Items]
Revenues																0	0	0
Expenses
Depreciation and amortization																0	0	0
Property transactions, net																0	0	0
Reimbursable expenses																0	0	0
Amortization of above market lease, net																0	0	0
Acquisition-related expenses																0	0	0
General and administrative																0	0	0
Expenses, net																0	0	0
Operating income (loss)																0	0	0
Equity in earnings of subsidiaries																(476,353)	(377,372)	(171,584)
Non-operating income (expense)
Interest income																(10,876)	0	0
Interest expense																10,876	0	0
Other non-operating																0	0	0
Non-operating income (expense)																0	0	0
Income from continuing operations before income taxes																(476,353)	(377,372)	(171,584)
Provision for income taxes																0	0	0
Net income (loss)																(476,353)	(377,372)	(171,584)
Income from discontinued operations																0
Other comprehensive income (loss)
Net income (loss)																(476,353)	(377,372)	(171,584)
Unrealized gain (loss) on cash flow hedges, net																0	0	0
Comprehensive income (loss)																(476,353)	(377,372)	(171,584)
Eliminations | Rental revenue
Condensed Income Statements, Captions [Line Items]
Revenues																0	0	0
Eliminations | Tenant reimbursements and other
Condensed Income Statements, Captions [Line Items]
Revenues																0	0	0
Operating Partnership | Reportable Legal Entities
Condensed Income Statements, Captions [Line Items]
Revenues																	0	0
Expenses
Depreciation and amortization																	0	0
Property transactions, net																	0	0
Reimbursable expenses																	0	0
Amortization of above market lease, net																	0	0
Acquisition-related expenses																	17,304	10,178
General and administrative																	12,189	9,896
Expenses, net																	29,493	20,074
Operating income (loss)																	(29,493)	(20,074)
Equity in earnings of subsidiaries																	377,372	171,584
Non-operating income (expense)
Interest income																	3,907	774
Interest expense																	(184,175)	(116,212)
Other non-operating																	(1,621)	(726)
Non-operating income (expense)																	(181,889)	(116,164)
Income from continuing operations before income taxes																	165,990	35,346
Provision for income taxes																	0	0
Net income (loss)																	165,990	35,346
Other comprehensive income (loss)
Net income (loss)																	165,990	35,346
Unrealized gain (loss) on cash flow hedges, net																	9,782	1,879
Comprehensive income (loss)																	175,772	37,225
Operating Partnership | Reportable Legal Entities | Rental revenue
Condensed Income Statements, Captions [Line Items]
Revenues																	0	0
Operating Partnership | Reportable Legal Entities | Tenant reimbursements and other
Condensed Income Statements, Captions [Line Items]
Revenues																	0	0
Co-Issuer | Reportable Legal Entities
Condensed Income Statements, Captions [Line Items]
Revenues																0	0	0
Expenses
Depreciation and amortization																0	0	0
Property transactions, net																0	0	0
Reimbursable expenses																0	0	0
Amortization of above market lease, net																0	0	0
Acquisition-related expenses																0	0	0
General and administrative																0	0	0
Expenses, net																0	0	0
Operating income (loss)																0	0	0
Equity in earnings of subsidiaries																0	0	0
Non-operating income (expense)
Interest income																0	0	0
Interest expense																0	0	0
Other non-operating																0	0	0
Non-operating income (expense)																0	0	0
Income from continuing operations before income taxes																0	0	0
Provision for income taxes																0	0	0
Net income (loss)																0	0	0
Income from discontinued operations																0
Other comprehensive income (loss)
Net income (loss)																0	0	0
Unrealized gain (loss) on cash flow hedges, net																0	0	0
Comprehensive income (loss)																0	0	0
Co-Issuer | Reportable Legal Entities | Rental revenue
Condensed Income Statements, Captions [Line Items]
Revenues																0	0	0
Co-Issuer | Reportable Legal Entities | Tenant reimbursements and other
Condensed Income Statements, Captions [Line Items]
Revenues																0	0	0
Guarantor Subsidiaries | Reportable Legal Entities
Condensed Income Statements, Captions [Line Items]
Revenues																869,495	765,695	467,548
Expenses
Depreciation and amortization																266,514	260,455	220,667
Property transactions, net																20,319	34,022	4,684
Reimbursable expenses																119,531	88,254	68,063
Amortization of above market lease, net																686	686	286
Acquisition-related expenses																0	0	0
General and administrative																0	0	0
Expenses, net																407,050	383,417	293,700
Operating income (loss)																462,445	382,278	173,848
Equity in earnings of subsidiaries																0	0	0
Non-operating income (expense)
Interest income																0	0	0
Interest expense																(10,876)	0	0
Other non-operating																0	0	0
Non-operating income (expense)																(10,876)	0	0
Income from continuing operations before income taxes																451,569	382,278	173,848
Provision for income taxes																(5,779)	(4,906)	(2,264)
Net income (loss)																445,790	377,372	171,584
Income from discontinued operations																30,563
Other comprehensive income (loss)
Net income (loss)																476,353	377,372	171,584
Unrealized gain (loss) on cash flow hedges, net																0	0	0
Comprehensive income (loss)																476,353	377,372	171,584
Guarantor Subsidiaries | Reportable Legal Entities | Rental revenue
Condensed Income Statements, Captions [Line Items]
Revenues																746,253	675,089	419,239
Guarantor Subsidiaries | Reportable Legal Entities | Tenant reimbursements and other
Condensed Income Statements, Captions [Line Items]
Revenues																123,242	90,606	48,309
MGP Operating Partnership
Condensed Income Statements, Captions [Line Items]
Revenues	226,011				216,659									655,193	652,888	869,495	765,695	467,548
Expenses
Depreciation and amortization	71,957				63,468									223,062	199,933	266,622	260,455	220,667
Property transactions, net	9,921				339									11,344	18,851	20,319	34,022	4,684
Reimbursable expenses	5,920				29,168									17,760	90,435	119,531	88,254	68,063
Amortization of above market lease, net	0				171									0	514	686	686	286
Acquisition-related expenses	92				1,931									8,891	4,603	6,149	17,304	10,178
General and administrative	4,476				3,358									12,305	10,021	16,048	12,189	9,896
Expenses, net	92,366				98,435									273,362	324,357	429,355	412,910	313,774
Operating income (loss)																440,140	352,785	153,774
Equity in earnings of subsidiaries	0				0									0	0	0	0
Non-operating income (expense)
Interest income	241				163									2,189	2,473	2,501	3,907	774
Interest expense	(63,048)				(58,743)									(190,973)	(157,249)	(215,532)	(184,175)	(116,212)
Other non-operating	(306)				(1,020)									(806)	(6,409)	(7,191)	(1,621)	(726)
Non-operating income (expense)	(63,113)				(59,600)									(189,590)	(161,185)	(220,222)	(181,889)	(116,164)
Income from continuing operations before income taxes	70,532				58,624									192,241	167,346	219,918	170,896	37,610
Provision for income taxes	(1,979)				(2,650)									(5,771)	(5,144)	(5,779)	(4,906)	(2,264)
Net income (loss)					55,974									186,470	162,202	214,139	165,990
Income from discontinued operations					13,949									16,216	13,949	30,563
Other comprehensive income (loss)
Net income (loss)	68,553	$ 67,769	$ 66,364	$ 68,551	69,923	$ 48,059	$ 58,169	$ 31,723	$ 43,700	$ 43,875	$ 46,692	$ (84,383)	$ 119,729	202,686	176,151	244,702	165,990	35,346
Unrealized gain (loss) on cash flow hedges, net	(19,270)				4,736									(65,657)	27,372	4,128	9,782	1,879
Comprehensive income (loss)	49,283				74,659									137,029	203,523	248,830	175,772	37,225
MGP Operating Partnership | Rental revenue
Condensed Income Statements, Captions [Line Items]
Revenues	219,847				186,564									636,575	559,690	746,253	675,089	419,239
MGP Operating Partnership | Tenant reimbursements and other
Condensed Income Statements, Captions [Line Items]
Revenues	6,164				30,095									18,618	93,198	123,242	$ 90,606	$ 48,309
MGP Operating Partnership | Eliminations
Condensed Income Statements, Captions [Line Items]
Revenues	0				0									0	0
Expenses
Depreciation and amortization	0				0									0	0
Property transactions, net	0				0									0	0
Reimbursable expenses	0				0									0	0
Amortization of above market lease, net					0										0
Acquisition-related expenses	0				0									0	0
General and administrative	0				0									0	0
Expenses, net	0				0									0	0
Equity in earnings of subsidiaries	(136,256)				(129,568)									(409,665)	(346,758)
Non-operating income (expense)
Interest income	0				(5,289)									(5,617)	(5,289)
Interest expense	0				5,289									5,617	5,289
Other non-operating	0				0									0	0
Non-operating income (expense)	0				0									0	0
Income from continuing operations before income taxes	(136,256)				(129,568)									(409,665)	(346,758)
Provision for income taxes	0				0									0	0
Net income (loss)					(129,568)									(409,665)	(346,758)
Income from discontinued operations					0									0	0
Other comprehensive income (loss)
Net income (loss)	(136,256)				(129,568)									(409,665)	(346,758)
Unrealized gain (loss) on cash flow hedges, net	0				0									0	0
Comprehensive income (loss)	(136,256)				(129,568)									(409,665)	(346,758)
MGP Operating Partnership | Eliminations | Rental revenue
Condensed Income Statements, Captions [Line Items]
Revenues	0				0									0	0
MGP Operating Partnership | Eliminations | Tenant reimbursements and other
Condensed Income Statements, Captions [Line Items]
Revenues	0				0									0	0
MGP Operating Partnership | Reportable Legal Entities
Condensed Income Statements, Captions [Line Items]
Revenues																0
Expenses
Depreciation and amortization																108
Property transactions, net																0
Reimbursable expenses																0
Amortization of above market lease, net																0
Acquisition-related expenses																6,149
General and administrative																16,048
Expenses, net																22,305
Operating income (loss)																(22,305)
Equity in earnings of subsidiaries																476,353
Non-operating income (expense)
Interest income																13,377
Interest expense																(215,532)
Other non-operating																(7,191)
Non-operating income (expense)																(209,346)
Income from continuing operations before income taxes																244,702
Provision for income taxes																0
Net income (loss)																244,702
Income from discontinued operations																0
Other comprehensive income (loss)
Net income (loss)																244,702
Unrealized gain (loss) on cash flow hedges, net																4,128
Comprehensive income (loss)																248,830
MGP Operating Partnership | Reportable Legal Entities | Rental revenue
Condensed Income Statements, Captions [Line Items]
Revenues																0
MGP Operating Partnership | Reportable Legal Entities | Tenant reimbursements and other
Condensed Income Statements, Captions [Line Items]
Revenues																$ 0
MGP Operating Partnership | Operating Partnership | Reportable Legal Entities
Condensed Income Statements, Captions [Line Items]
Revenues	0				0									0	0
Expenses
Depreciation and amortization	22				45									65	87
Property transactions, net	0				0									0	0
Reimbursable expenses	0				0									0	0
Amortization of above market lease, net					0										0
Acquisition-related expenses	92				1,931									8,891	4,603
General and administrative	4,476				3,358									12,305	10,021
Expenses, net	4,590				5,334									21,261	14,711
Equity in earnings of subsidiaries	136,256				129,568									409,665	346,758
Non-operating income (expense)
Interest income	241				5,452									7,806	7,762
Interest expense	(63,048)				(58,743)									(190,973)	(157,249)
Other non-operating	(306)				(1,020)									(806)	(6,409)
Non-operating income (expense)	(63,113)				(54,311)									(183,973)	(155,896)
Income from continuing operations before income taxes	68,553				69,923									204,431	176,151
Provision for income taxes	0				0									(1,745)	0
Net income (loss)					69,923									202,686	176,151
Income from discontinued operations					0									0	0
Other comprehensive income (loss)
Net income (loss)	68,553				69,923									202,686	176,151
Unrealized gain (loss) on cash flow hedges, net	(19,270)				4,736									(65,657)	27,372
Comprehensive income (loss)	49,283				74,659									137,029	203,523
MGP Operating Partnership | Operating Partnership | Reportable Legal Entities | Rental revenue
Condensed Income Statements, Captions [Line Items]
Revenues	0				0									0	0
MGP Operating Partnership | Operating Partnership | Reportable Legal Entities | Tenant reimbursements and other
Condensed Income Statements, Captions [Line Items]
Revenues	0				0									0	0
MGP Operating Partnership | Co-Issuer | Reportable Legal Entities
Condensed Income Statements, Captions [Line Items]
Revenues	0				0									0	0
Expenses
Depreciation and amortization	0				0									0	0
Property transactions, net	0				0									0	0
Reimbursable expenses	0				0									0	0
Amortization of above market lease, net					0										0
Acquisition-related expenses	0				0									0	0
General and administrative	0				0									0	0
Expenses, net	0				0									0	0
Equity in earnings of subsidiaries	0				0									0	0
Non-operating income (expense)
Interest income	0				0									0	0
Interest expense	0				0									0	0
Other non-operating	0				0									0	0
Non-operating income (expense)	0				0									0	0
Income from continuing operations before income taxes	0				0									0	0
Provision for income taxes	0				0									0	0
Net income (loss)					0									0	0
Income from discontinued operations					0									0	0
Other comprehensive income (loss)
Net income (loss)	0				0									0	0
Unrealized gain (loss) on cash flow hedges, net	0				0									0	0
Comprehensive income (loss)	0				0									0	0
MGP Operating Partnership | Co-Issuer | Reportable Legal Entities | Rental revenue
Condensed Income Statements, Captions [Line Items]
Revenues	0				0									0	0
MGP Operating Partnership | Co-Issuer | Reportable Legal Entities | Tenant reimbursements and other
Condensed Income Statements, Captions [Line Items]
Revenues	0				0									0	0
MGP Operating Partnership | Guarantor Subsidiaries | Reportable Legal Entities
Condensed Income Statements, Captions [Line Items]
Revenues	226,011				216,659									655,193	652,888
Expenses
Depreciation and amortization	71,935				63,423									222,997	199,846
Property transactions, net	9,921				339									11,344	18,851
Reimbursable expenses	5,920				29,168									17,760	90,435
Amortization of above market lease, net					171										514
Acquisition-related expenses	0				0									0	0
General and administrative	0				0									0	0
Expenses, net	87,776				93,101									252,101	309,646
Equity in earnings of subsidiaries	0				0									0	0
Non-operating income (expense)
Interest income	0				0									0	0
Interest expense	0				(5,289)									(5,617)	(5,289)
Other non-operating	0				0									0	0
Non-operating income (expense)	0				(5,289)									(5,617)	(5,289)
Income from continuing operations before income taxes	138,235				118,269									397,475	337,953
Provision for income taxes	(1,979)				(2,650)									(4,026)	(5,144)
Net income (loss)					115,619									393,449	332,809
Income from discontinued operations					13,949									16,216	13,949
Other comprehensive income (loss)
Net income (loss)	136,256				129,568									409,665	346,758
Unrealized gain (loss) on cash flow hedges, net	0				0									0	0
Comprehensive income (loss)	136,256				129,568									409,665	346,758
MGP Operating Partnership | Guarantor Subsidiaries | Reportable Legal Entities | Rental revenue
Condensed Income Statements, Captions [Line Items]
Revenues	219,847				186,564									636,575	559,690
MGP Operating Partnership | Guarantor Subsidiaries | Reportable Legal Entities | Tenant reimbursements and other
Condensed Income Statements, Captions [Line Items]
Revenues	$ 6,164				$ 30,095									$ 18,618	$ 93,198

Condensed Consolidating Finan_5

Condensed Consolidating Financial Information - Consolidating Statement of Cash Flows Information (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended		12 Months Ended
	Jun. 30, 2019	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Cash flows from operating activities
Net cash provided by (used in) operating activities		$ (84,517)	$ 424,837	$ 556,801	$ 482,578	$ 297,781
Acquisition of Northfield	$ (298,957)	0	(1,068,337)	(1,068,336)	0	0
Cash flows from investing activities
Capital expenditures for property and equipment		0	(191)	(192)	(488)	(138,987)
MGM National Harbor Transaction				0	(462,500)	0
Net cash provided by (used in) investing activities		3,779	(1,068,528)	(1,068,528)	(462,988)	(138,987)
Cash flows from financing activities
Net borrowings (repayments) under bank credit facility		(566,813)	747,375	727,750	(41,875)	(16,750)
Proceeds from issuance of debt		750,000	0	0	350,000	3,700,000
Deferred financing costs		(9,983)	(17,490)	(17,490)	(5,598)	(77,163)
Repayment of assumed debt and bridge facilities		(245,950)	0	0	(425,000)	(4,544,850)
Issuance of Operating Partnership units		699,362	0	0	404,685	1,207,500
Dividends and distributions paid		(395,005)	(337,865)	(454,260)	(385,435)	(150,829)
Other		(1,342)	0
Net cash transfers from Parent				0	0	158,822
Net cash provided by (used in) financing activities		230,269	392,020	256,000	(120,360)	201,698
Cash flows from discontinued operations, net
Cash flows provided by operating activities, net		15,591	8,250	23,406	0	0
Cash flows provided by investing activities, net		(12)	33,199	32,416	0	0
Cash flows used in financing activities, net		(37,900)	0	0	0	0
Net cash provided by (used in) discontinued operations		(22,321)	41,449	55,822	0	0
Cash and cash equivalents
Net increase (decrease) for the period		149,531	(251,671)	(255,727)	(100,770)	360,492
Balance, beginning of period		3,995	259,722	259,722	360,492	0
Balance, end of period		153,526	8,051	3,995	259,722	360,492
MGP Operating Partnership
Cash flows from operating activities
Net cash provided by (used in) operating activities		(84,517)	424,837	556,801	482,578	297,781
Proceeds from Northfield OpCo Transaction		3,779
Acquisition of Northfield		0	(1,068,337)	(1,068,336)	0	0
Cash flows from investing activities
Capital expenditures for property and equipment		0	(191)	(192)	(488)	(138,987)
MGM National Harbor Transaction				0	(462,500)	0
Net cash provided by (used in) investing activities		3,779	(1,068,528)	(1,068,528)	(462,988)	(138,987)
Cash flows from financing activities
Net borrowings (repayments) under bank credit facility		(566,813)	747,375	727,750	(41,875)	(16,750)
Proceeds from issuance of debt		750,000	0	0	350,000	3,700,000
Deferred financing costs		(9,983)	(17,490)	(17,490)	(5,598)	(77,163)
Repayment of assumed debt and bridge facilities		(245,950)	0	0	(425,000)	(4,544,850)
Repayment of debt principal					(41,875)	(16,750)
Issuance of Operating Partnership units		699,362	0	0	387,548	1,132,468
Proceeds from purchase of Operating Partnership units by MGP					387,548	1,132,468
Dividends and distributions paid		(395,005)	(337,865)	(454,260)	(385,435)	(150,829)
Cash received by Parent on behalf of Guarantor Subsidiaries		0	0	0	0	0
Other		(1,342)	0
Net cash transfers from Parent				0	0	158,822
Net cash provided by (used in) financing activities		230,269	392,020	256,000	(120,360)	201,698
Cash flows from discontinued operations, net
Cash flows provided by operating activities, net		15,591	8,250	23,406	0	0
Cash flows provided by investing activities, net		(12)	33,199	32,416	0	0
Cash flows used in financing activities, net		(37,900)	0	0	0	0
Net cash provided by (used in) discontinued operations		(22,321)	41,449	55,822	0	0
Change in cash and cash equivalents classified as assets held for sale		(22,321)	41,449	55,822
Cash and cash equivalents
Net increase (decrease) for the period		149,531	(251,671)	(255,727)	(100,770)	360,492
Balance, beginning of period		3,995	259,722	259,722	360,492	0
Balance, end of period		153,526	8,051	3,995	259,722	360,492
MGP Operating Partnership | Eliminations
Cash flows from operating activities
Net cash provided by (used in) operating activities		0	0	0	0	0
Proceeds from Northfield OpCo Transaction		0
Acquisition of Northfield				0
Cash flows from investing activities
Capital expenditures for property and equipment			0	0	0	0
MGM National Harbor Transaction					0
Net cash provided by (used in) investing activities		0	0	0	0	0
Cash flows from financing activities
Net borrowings (repayments) under bank credit facility		0	0	0
Proceeds from issuance of debt		0			0	0
Deferred financing costs		0	0	0	0	0
Repayment of assumed debt and bridge facilities		0			0	0
Repayment of debt principal					0	0
Issuance of Operating Partnership units		0
Proceeds from purchase of Operating Partnership units by MGP					0	0
Dividends and distributions paid		0	0	0	0	0
Cash received by Parent on behalf of Guarantor Subsidiaries		0	0	0	0	0
Other		0
Net cash transfers from Parent						0
Net cash provided by (used in) financing activities		0	0	0	0	0
Cash flows from discontinued operations, net
Cash flows provided by operating activities, net		0	0
Cash flows provided by investing activities, net		0	0
Cash flows used in financing activities, net		0	0
Net cash provided by (used in) discontinued operations		0	0	0
Change in cash and cash equivalents classified as assets held for sale		0	0	0
Cash and cash equivalents
Net increase (decrease) for the period		0	0	0	0	0
Balance, beginning of period		0	0	0	0	0
Balance, end of period		0	0	0	0	0
MGP Operating Partnership | Operating Partnership | Reportable Legal Entities
Cash flows from operating activities
Net cash provided by (used in) operating activities		(762,230)	(149,511)	(210,132)	(198,925)	(99,884)
Proceeds from Northfield OpCo Transaction		3,779
Acquisition of Northfield			(1,068,337)	(1,068,336)
Cash flows from investing activities
Capital expenditures for property and equipment			(191)	(192)	(488)	0
MGM National Harbor Transaction					(462,500)
Net cash provided by (used in) investing activities		3,779	(1,068,528)	(1,068,528)	(462,988)	0
Cash flows from financing activities
Net borrowings (repayments) under bank credit facility		(566,813)	747,375	727,750
Proceeds from issuance of debt		750,000			350,000	3,700,000
Deferred financing costs		(9,983)	(17,490)	(17,490)	(5,598)	(77,163)
Repayment of assumed debt and bridge facilities		(245,950)			(425,000)	(4,544,850)
Repayment of debt principal					(41,875)	(16,750)
Issuance of Operating Partnership units		699,362
Proceeds from purchase of Operating Partnership units by MGP					387,548	1,132,468
Dividends and distributions paid		(395,005)	(337,865)	(454,260)	(385,435)	(150,829)
Cash received by Parent on behalf of Guarantor Subsidiaries		677,713	574,348	766,933	681,503	417,500
Other		(1,342)
Net cash transfers from Parent						0
Net cash provided by (used in) financing activities		907,982	966,368	1,022,933	561,143	460,376
Cash flows from discontinued operations, net
Cash flows provided by operating activities, net		0	0	0
Cash flows provided by investing activities, net		0	0	0
Cash flows used in financing activities, net		0	0	0
Net cash provided by (used in) discontinued operations		0	0	0
Change in cash and cash equivalents classified as assets held for sale		0	0	0
Cash and cash equivalents
Net increase (decrease) for the period		149,531	(251,671)	(255,727)	(100,770)	360,492
Balance, beginning of period		3,995	259,722	259,722	360,492	0
Balance, end of period		153,526	8,051	3,995	259,722	360,492
MGP Operating Partnership | Co-Issuer | Reportable Legal Entities
Cash flows from operating activities
Net cash provided by (used in) operating activities		0	0	0	0	0
Proceeds from Northfield OpCo Transaction		0
Acquisition of Northfield			0	0
Cash flows from investing activities
Capital expenditures for property and equipment			0	0	0	0
MGM National Harbor Transaction					0
Net cash provided by (used in) investing activities		0	0	0	0	0
Cash flows from financing activities
Net borrowings (repayments) under bank credit facility		0	0	0
Proceeds from issuance of debt		0			0	0
Deferred financing costs		0	0	0	0	0
Repayment of assumed debt and bridge facilities		0			0	0
Repayment of debt principal					0	0
Issuance of Operating Partnership units		0
Proceeds from purchase of Operating Partnership units by MGP					0	0
Dividends and distributions paid		0	0	0	0	0
Cash received by Parent on behalf of Guarantor Subsidiaries		0	0	0	0	0
Other		0
Net cash transfers from Parent						0
Net cash provided by (used in) financing activities		0	0	0	0	0
Cash flows from discontinued operations, net
Cash flows provided by operating activities, net		0	0	0
Cash flows provided by investing activities, net		0	0	0
Cash flows used in financing activities, net		0	0	0
Net cash provided by (used in) discontinued operations		0	0	0
Change in cash and cash equivalents classified as assets held for sale		0	0	0
Cash and cash equivalents
Net increase (decrease) for the period		0	0	0	0	0
Balance, beginning of period		0	0	0	0	0
Balance, end of period		0	0	0	0	0
MGP Operating Partnership | Guarantor Subsidiaries | Reportable Legal Entities
Cash flows from operating activities
Net cash provided by (used in) operating activities		677,713	574,348	766,933	681,503	397,665
Proceeds from Northfield OpCo Transaction		0
Acquisition of Northfield			0	0
Cash flows from investing activities
Capital expenditures for property and equipment			0	0	0	(138,987)
MGM National Harbor Transaction					0
Net cash provided by (used in) investing activities		0	0	0	0	(138,987)
Cash flows from financing activities
Net borrowings (repayments) under bank credit facility		0	0	0
Proceeds from issuance of debt		0			0	0
Deferred financing costs		0	0	0	0	0
Repayment of assumed debt and bridge facilities		0			0	0
Repayment of debt principal					0	0
Issuance of Operating Partnership units		0
Proceeds from purchase of Operating Partnership units by MGP					0	0
Dividends and distributions paid		0	0	0	0	0
Cash received by Parent on behalf of Guarantor Subsidiaries		(677,713)	(574,348)	(766,933)	(681,503)	(417,500)
Other		0
Net cash transfers from Parent						158,822
Net cash provided by (used in) financing activities		(677,713)	(574,348)	(766,933)	(681,503)	(258,678)
Cash flows from discontinued operations, net
Cash flows provided by operating activities, net		15,591	8,250	23,406
Cash flows provided by investing activities, net		(12)	33,199	32,416
Cash flows used in financing activities, net		(37,900)	0	0
Net cash provided by (used in) discontinued operations		(22,321)	41,449	55,822
Change in cash and cash equivalents classified as assets held for sale		(22,321)	41,449	55,822
Cash and cash equivalents
Net increase (decrease) for the period		0	0	55,822	0	0
Balance, beginning of period		0	0	0	0	0
Balance, end of period		$ 0	$ 0	$ 0	$ 0	$ 0

MGP Selected Quarterly Financ_3

MGP Selected Quarterly Financial Results (Unaudited) - Summary of Quarterly Financial Results (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended											4 Months Ended	8 Months Ended	9 Months Ended		12 Months Ended
	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Apr. 24, 2016	Dec. 31, 2016	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Revenues				$ 216,607	$ 216,659	$ 220,390	$ 215,839	$ 214,542	$ 182,798	$ 184,456	$ 183,899					$ 869,495	$ 765,695
Net income	$ 68,553	$ 67,769	$ 66,364	68,551	69,923	48,059	58,169	31,723	43,700	43,875	46,692	$ (84,383)	$ 119,729	$ 202,686	$ 176,151	244,702	165,990	$ 35,346
Net income attributable to Class A shareholders	$ 22,515			$ 18,605	$ 19,484	$ 13,146	$ 15,830	$ 8,722	$ 11,025	$ 10,680	$ 11,348		$ 29,938	$ 64,328	$ 48,460	$ 67,065	$ 41,775	$ 29,938
Class A Shares
Net income per Class A share (basic) (in dollars per share)	$ 0.24			$ 0.26	$ 0.27	$ 0.19	$ 0.22	$ 0.12	$ 0.18	$ 0.19	$ 0.20			$ 0.72	$ 0.68	$ 0.94	$ 0.68	$ 0.52
Net income per Class A share (diluted) (in dollars per share)	$ 0.24			$ 0.26	$ 0.27	$ 0.18	$ 0.22	$ 0.12	$ 0.18	$ 0.18	$ 0.20			$ 0.72	$ 0.68	$ 0.94	$ 0.67	$ 0.52

MGP Selected Quarterly Financ_4

MGP Selected Quarterly Financial Results (Unaudited) - Narrative (Detail) - MGM National Harbor $ in Millions	Oct. 05, 2017USD ($)
Master Lease - Rent Increase
Segment Reporting Information [Line Items]
Rental revenues under master lease	$ 95
Base Rent Increase
Segment Reporting Information [Line Items]
Rental revenues under master lease	85.5
Percentage Rent Increase
Segment Reporting Information [Line Items]
Rental revenues under master lease	$ 9.5

Operating Partnership Selecte_3

Operating Partnership Selected Quarterly Financial Results (Unaudited) - Summary of Quarterly Financial Results (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended											4 Months Ended	8 Months Ended	9 Months Ended		12 Months Ended
	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Apr. 24, 2016	Dec. 31, 2016	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Segment Reporting Information [Line Items]
Revenues				$ 216,607	$ 216,659	$ 220,390	$ 215,839	$ 214,542	$ 182,798	$ 184,456	$ 183,899					$ 869,495	$ 765,695
Net income	$ 68,553	$ 67,769	$ 66,364	68,551	69,923	48,059	58,169	31,723	43,700	43,875	46,692	$ (84,383)	$ 119,729	$ 202,686	$ 176,151	244,702	165,990	$ 35,346
MGP Operating Partnership
Segment Reporting Information [Line Items]
Revenues				216,607	216,659	220,390	215,839	214,542	182,798	184,456	183,899					869,495	765,695
Net income	$ 68,553	$ 67,769	$ 66,364	$ 68,551	$ 69,923	$ 48,059	$ 58,169	$ 31,723	$ 43,700	$ 43,875	$ 46,692	$ (84,383)	$ 119,729	$ 202,686	$ 176,151	$ 244,702	$ 165,990	$ 35,346
Net income per Operating Partnership unit (basic in dollars per share)	$ 0.23			$ 0.26	$ 0.26	$ 0.18	$ 0.22	$ 0.12	$ 0.18	$ 0.18	$ 0.19			$ 0.70	$ 0.66	$ 0.92	$ 0.67	$ 0.52
Net income per Operating Partnership unit (diluted in dollars per share)	$ 0.23			$ 0.26	$ 0.26	$ 0.18	$ 0.22	$ 0.12	$ 0.18	$ 0.18	$ 0.19			$ 0.70	$ 0.66	$ 0.92	$ 0.66	$ 0.52

Schedule III - Real Estate an_2

Schedule III - Real Estate and Accumulated Depreciation - Summary of Real Estate Properties (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Gross Amount at Which Carried at Close of Period
Total	$ 13,318,334	$ 12,655,847	$ 11,468,170	$ 9,965,185
Accumulated Depreciation	(2,812,205)	$ (2,633,909)	$ (2,388,492)	$ (2,171,546)
Aggregate cost of land, buildings, and improvements for federal income tax purposes	9,400,000
Investment Properties
Acquisition Costs
Land	4,536,013
Building, Improvements and Other	8,821,173
Costs Capitalized Subsequent to Acquisition
Land	0
Building, Improvements and Other	144,713
Gross Amount at Which Carried at Close of Period
Land	4,536,013
Building, Improvements and Other	8,781,640
Total	13,317,653
Accumulated Depreciation	(2,812,097)
Investment Properties Plus Corporate Property
Acquisition Costs
Land	4,536,013
Building, Improvements and Other	8,821,661
Costs Capitalized Subsequent to Acquisition
Land	0
Building, Improvements and Other	144,905
Gross Amount at Which Carried at Close of Period
Land	4,536,013
Building, Improvements and Other	8,782,321
Total	13,318,334
Accumulated Depreciation	(2,812,205)
New York-New York | Investment Properties
Acquisition Costs
Land	149,984
Building, Improvements and Other	484,001
Costs Capitalized Subsequent to Acquisition
Land	0
Building, Improvements and Other	0
Gross Amount at Which Carried at Close of Period
Land	149,984
Building, Improvements and Other	484,536
Total	634,520
Accumulated Depreciation	(296,527)
The Mirage | Investment Properties
Acquisition Costs
Land	1,017,562
Building, Improvements and Other	760,222
Costs Capitalized Subsequent to Acquisition
Land	0
Building, Improvements and Other	0
Gross Amount at Which Carried at Close of Period
Land	1,017,562
Building, Improvements and Other	747,479
Total	1,765,041
Accumulated Depreciation	(484,617)
Mandalay Bay | Investment Properties
Acquisition Costs
Land	1,199,785
Building, Improvements and Other	1,882,381
Costs Capitalized Subsequent to Acquisition
Land	0
Building, Improvements and Other	0
Gross Amount at Which Carried at Close of Period
Land	1,199,785
Building, Improvements and Other	1,871,540
Total	3,071,325
Accumulated Depreciation	(733,704)
Luxor | Investment Properties
Acquisition Costs
Land	440,685
Building, Improvements and Other	710,796
Costs Capitalized Subsequent to Acquisition
Land	0
Building, Improvements and Other	0
Gross Amount at Which Carried at Close of Period
Land	440,685
Building, Improvements and Other	704,484
Total	1,145,169
Accumulated Depreciation	(350,834)
Excalibur | Investment Properties
Acquisition Costs
Land	814,805
Building, Improvements and Other	342,685
Costs Capitalized Subsequent to Acquisition
Land	0
Building, Improvements and Other	43,945
Gross Amount at Which Carried at Close of Period
Land	814,805
Building, Improvements and Other	384,036
Total	1,198,841
Accumulated Depreciation	(144,345)
Park MGM | Investment Properties
Acquisition Costs
Land	291,035
Building, Improvements and Other	376,625
Costs Capitalized Subsequent to Acquisition
Land	0
Building, Improvements and Other	100,768
Gross Amount at Which Carried at Close of Period
Land	291,035
Building, Improvements and Other	322,875
Total	613,910
Accumulated Depreciation	(87,453)
Beau Rivage | Investment Properties
Acquisition Costs
Land	104,945
Building, Improvements and Other	561,457
Costs Capitalized Subsequent to Acquisition
Land	0
Building, Improvements and Other	0
Gross Amount at Which Carried at Close of Period
Land	104,945
Building, Improvements and Other	559,210
Total	664,155
Accumulated Depreciation	(258,113)
MGM Grand Detroit | Investment Properties
Acquisition Costs
Land	52,509
Building, Improvements and Other	597,324
Costs Capitalized Subsequent to Acquisition
Land	0
Building, Improvements and Other	0
Gross Amount at Which Carried at Close of Period
Land	52,509
Building, Improvements and Other	597,324
Total	649,833
Accumulated Depreciation	(177,119)
Gold Strike Tunica | Investment Properties
Acquisition Costs
Land	3,609
Building, Improvements and Other	179,146
Costs Capitalized Subsequent to Acquisition
Land	0
Building, Improvements and Other	0
Gross Amount at Which Carried at Close of Period
Land	3,609
Building, Improvements and Other	178,578
Total	182,187
Accumulated Depreciation	(88,475)
Borgata | Investment Properties
Acquisition Costs
Land	35,568
Building, Improvements and Other	1,264,432
Costs Capitalized Subsequent to Acquisition
Land	0
Building, Improvements and Other	0
Gross Amount at Which Carried at Close of Period
Land	35,568
Building, Improvements and Other	1,254,782
Total	1,290,350
Accumulated Depreciation	(87,997)
MGM National Harbor | Investment Properties
Acquisition Costs
Land	0
Building, Improvements and Other	1,183,909
Costs Capitalized Subsequent to Acquisition
Land	0
Building, Improvements and Other	0
Gross Amount at Which Carried at Close of Period
Land	0
Building, Improvements and Other	1,199,839
Total	1,199,839
Accumulated Depreciation	(83,837)
The Park | Investment Properties
Acquisition Costs
Land	33,026
Building, Improvements and Other	101,353
Costs Capitalized Subsequent to Acquisition
Land	0
Building, Improvements and Other	0
Gross Amount at Which Carried at Close of Period
Land	33,026
Building, Improvements and Other	100,115
Total	133,141
Accumulated Depreciation	(13,638)
MGP Corporate Office | Corporate Property
Acquisition Costs
Land	0
Building, Improvements and Other	488
Costs Capitalized Subsequent to Acquisition
Land	0
Building, Improvements and Other	192
Gross Amount at Which Carried at Close of Period
Land	0
Building, Improvements and Other	681
Total	681
Accumulated Depreciation	(108)
MGM Northfield Park | Investment Properties
Acquisition Costs
Land	392,500
Building, Improvements and Other	376,842
Costs Capitalized Subsequent to Acquisition
Land	0
Building, Improvements and Other	0
Gross Amount at Which Carried at Close of Period
Land	392,500
Building, Improvements and Other	376,842
Total	769,342
Accumulated Depreciation	$ (5,438)

Schedule III - Real Estate an_3

Schedule III - Real Estate and Accumulated Depreciation - Summary of Depreciable Lives (Detail)	12 Months Ended
	Dec. 31, 2018
Buildings and building improvements | Minimum
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Depreciable lives	20 years
Buildings and building improvements | Maximum
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Depreciable lives	40 years
Land improvements | Minimum
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Depreciable lives	10 years
Land improvements | Maximum
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Depreciable lives	20 years
Fixtures and integral equipment | Minimum
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Depreciable lives	3 years
Fixtures and integral equipment | Maximum
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items]
Depreciable lives	20 years

Schedule III - Real Estate an_4

Schedule III - Real Estate and Accumulated Depreciation - Reconciliation of Real Estate (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate [Roll Forward]
Balance at beginning of year	$ 12,655,847	$ 11,468,170	$ 9,965,185
Additions	788,850	1,273,776	1,511,390
Dispositions and write-offs	(105,646)	(86,905)	(8,405)
Other	(20,717)	806	0
Balance at end of year	13,318,334	12,655,847	11,468,170
MGM National Harbor Transaction
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate [Roll Forward]
Additions		$ 1,200,000
Borgata
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate [Roll Forward]
Additions			$ 1,300,000
MGM Northfield Park
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate [Roll Forward]
Additions	$ 769,300

Schedule III - Real Estate an_5

Schedule III - Real Estate and Accumulated Depreciation - Reconciliation of Accumulated Depreciation (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate, Accumulated Depreciation [Roll Forward]
Balance at beginning of year	$ (2,633,909)	$ (2,388,492)	$ (2,171,546)
Depreciation expense	(266,622)	(260,455)	(220,667)
Dispositions and write-offs	85,327	52,883	3,721
Other	2,999	(37,845)	0
Balance at end of year	$ (2,812,205)	$ (2,633,909)	$ (2,388,492)