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Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Aggregate dividends paid during the period for each share of common stock outstanding.

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Monetary value of common stock allocated to investors to buy shares of a new issue of common stock before they are offered to the public. When stock is sold on a subscription basis, the issuer does not initially receive the total proceeds. In general, the issuer does not issue the shares to the investor until it receives the entire proceeds.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Cash received on stock transaction after deduction of issuance costs.

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The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

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No definition available.

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The number of units or equivalent units outstanding for all classes.

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Shareholders' Equity and Partners' Capital - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions					3 Months Ended
	Jul. 15, 2019	Apr. 01, 2019	Mar. 07, 2019	Jan. 31, 2019	Jun. 30, 2019	Jun. 29, 2019	Apr. 30, 2019	Apr. 02, 2019	Mar. 06, 2019	Jan. 30, 2019	Jan. 29, 2019	Jan. 28, 2019
Class A Shares
Class of Stock [Line Items]
Sale of Stock, Number of Shares Issued in Transaction ( in shares )					2,100,000
Sale of Stock, Consideration Received on Transaction					$ 64.9
Common Stock, Value, Subscriptions							$ 300.0
Public Stock Offering \| Class A Shares
Class of Stock [Line Items]
Sale of Stock, Number of Shares Issued in Transaction ( in shares )				19,600,000
Sale of Stock, Consideration Received on Transaction				$ 548.4
Equity Method Investment, Ownership Percentage				30.30%						25.40%
Over-Allotment Option \| Class A Shares
Class of Stock [Line Items]
Sale of Stock, Number of Shares Issued in Transaction ( in shares )				2,600,000
Empire City
Class of Stock [Line Items]
Partnership Interest ( in units )											12,900,000
Equity Method Investment, Ownership Percentage											25.40%	26.70%
Park MGM Lease Transaction
Class of Stock [Line Items]
Equity Method Investment, Ownership Percentage			30.20%						30.30%
Northfield
Class of Stock [Line Items]
Equity Method Investment, Ownership Percentage		30.20%			31.70%	31.20%		31.20%
Subsequent Event \| Class A Shares
Class of Stock [Line Items]
Dividends	$ 0.4675
Common Stock, Dividends, Per Share, Cash Received	$ 0.4675
Operating Partnership Units
Class of Stock [Line Items]
Business Combination, Consideration Transferred, Equity Interests Issued and Issuable					$ 2.1
Operating Partnership Units \| Park MGM Lease Transaction
Class of Stock [Line Items]
Business Combination, Consideration Transferred, Equity Interests Issued and Issuable			$ 1.0
Operating Partnership Units \| Northfield
Class of Stock [Line Items]
Business Combination, Consideration Transferred, Equity Interests Issued and Issuable		$ 9.4