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Business Combination, Consideration Transferred Carry Over Value

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Percentage of voting equity interests acquired at the acquisition date in the business combination.

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount of liabilities incurred by the acquirer as part of consideration transferred in a business combination.

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Acquisitions and dispositions - Narrative (Details) - USD ($) $ in Thousands				6 Months Ended
	Apr. 01, 2019	Jan. 29, 2019	Jul. 06, 2018	Jun. 30, 2019	Jun. 30, 2018
Business Acquisition [Line Items]
Business Combination, Contingent Consideration Arrangements, Change in Amount of Contingent Consideration, Liability		$ 9,400
Amounts drawn on debt instruments during period				$ 750,000	$ 0
Empire City
Business Acquisition [Line Items]
Liabilities incurred		$ 246,000
Partnership Interest ( in units )		12,900,000
Business Combination, Consideration Transferred Carryover Value		$ 625,000
Purchase price		$ 634,400
Northfield
Business Acquisition [Line Items]
Business Combination, Consideration Transferred Carryover Value	$ 292,300
Membership interest acquired ( as a percent )			100.00%
Purchase price	$ 305,200		$ 1,100,000