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Carrying amount (original costs adjusted for previously recognized amortization and impairment) as of the balance sheet date for the capitalized costs to acquire rights under a license arrangement (for example, to sell specified products in a specified territory) having an indefinite period of benefit.

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BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) - USD ($) $ in Thousands		3 Months Ended			9 Months Ended
	Jan. 25, 2019	Jun. 30, 2019	Dec. 31, 2018	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Sep. 30, 2018
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Depreciation and amortization		$ 22,810		$ 20,664	$ 92,682	$ 60,699
Variable consideration of gaming revenues					70.00%
Payment for license fees	$ 8,000
Indefinite useful life intangible asset	$ 8,000
Other long-term liabilities		108,817			$ 108,817		$ 4,618
Senior Secured Credit Facility - Revolving \| Revolving Credit Facility \| Carrying Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Credit facility value		114,000			114,000
Senior Secured Credit Facility - Revolving \| Revolving Credit Facility \| Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Credit facility value		107,588			107,588
Senior Secured Credit Facility - Term Loan A \| Credit Facility \| Carrying Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Credit facility value		274,370			274,370
Senior Secured Credit Facility - Term Loan A \| Credit Facility \| Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Credit facility value		267,324			267,324
Senior Secured Credit Facility - Term Loan B \| Credit Facility \| Carrying Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Credit facility value		806,627			806,627
Senior Secured Credit Facility - Term Loan B \| Credit Facility \| Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Credit facility value		$ 766,775			$ 766,775
2016 7 7/8% Senior Unsecured Notes \| Senior Unsecured Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Note stated interest rate		7.875%			7.875%
2016 7 7/8% Senior Unsecured Notes \| Senior Unsecured Notes \| Carrying Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Note value		$ 490,056			$ 490,056
2016 7 7/8% Senior Unsecured Notes \| Senior Unsecured Notes \| Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Note value		489,375			489,375
MGE Niagara Credit Facility \| Credit Facility \| Carrying Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Note value		75,140			75,140
MGE Niagara Credit Facility \| Credit Facility \| Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Note value		75,140			75,140
Useful life adjustment
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Depreciation and amortization			$ 6,300
Useful life adjustment
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Depreciation and amortization		21,600
Unibet
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Other long-term liabilities		8,000			8,000
Other Current Assets
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Contract with customer, asset		541			541
Other Assets
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Contract with customer, noncurrent asset		$ 4,100			$ 4,100