Available-for-sale Securities, Change in Share Price, Percent

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Business Combination, Consideration Transferred, Working Capital Adjustment

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Debt Instrument, Interest Rate Floor

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Debt Instrument, Issue Price, Percentage of Principal Amount

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Equity Investee Ownership Interest in Joint Venture

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The change in unrealized holding gain (loss), net of tax, on available-for-sale securities included in a separate component of shareholders' equity during the period.

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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 long-term debt due after one year or the normal operating cycle, if longer, assumed at the acquisition date.

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- Definition

Face amount or stated value per share of common stock.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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Face (par) amount of debt instrument at time of issuance.

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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Percentage of principal amount of debt redeemed.

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Face (par) amount of the original debt instrument that was repurchased.

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Represents the aggregate of total long-term debt, including current maturities and short-term debt.

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Total investments in (A) an entity in which the entity has significant influence, but does not have control, (B) subsidiaries that are not required to be consolidated and are accounted for using the equity and or cost method, and (C) an entity in which the reporting entity shares control of the entity with another party or group. Includes long-term advances receivable from a party that is affiliated with the reporting entity by means of direct or indirect ownership.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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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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Marketable Securities, Eldorado Resorts, Inc. (Details) - USD ($)				9 Months Ended	12 Months Ended		14 Months Ended
	Nov. 24, 2015	Jul. 23, 2015	Sep. 19, 2014	Nov. 30, 2015	Dec. 31, 2021	Dec. 31, 2018	Nov. 30, 2015	Sep. 30, 2015	Jul. 13, 2015	Feb. 28, 2015	Dec. 31, 2007
Schedule of Equity Method Investments [Line Items]
Investment											$ 38,000,000
Eldorado
Schedule of Equity Method Investments [Line Items]
Equity method investee percentage ownership in JV (percent)				17.0359%			17.0359%
Investment				$ 39,054,964			$ 39,054,964			$ 18,540,023
ERI [Member]
Schedule of Equity Method Investments [Line Items]
Common stock issued (shares)			4,030,440
Par value (usd per share)			$ 0.00001
Equity method investee percentage ownership in JV (percent)			8.60%
Change in net unrealized holding gain (loss)			$ (7,100,000)	$ 20,500,000			$ 22,400,000
Change in share price, percent							11.00%
ERI [Member] \| Silver Legacy Resort Casino
Schedule of Equity Method Investments [Line Items]
Cash consideration	$ 80,200,000
Purchase price	72,500,000
Working capital adjustment	7,700,000
Liabilities assumed, credit facility	$ 80,500,000
Senior Notes \| Senior Secured Notes due 2019 \| ERI [Member] \| Eldorado
Schedule of Equity Method Investments [Line Items]
Principal outstanding									$ 168,000,000
Interest rate (percent)									8.625%
Debt instrument, redemption price, percentage of principal amount redeemed		104.792%
Debt instrument, repurchased face amount		$ 130,000,000
Senior Notes \| Senior Secured Second Lien Notes due 2019 \| ERI [Member] \| Eldorado
Schedule of Equity Method Investments [Line Items]
Principal outstanding									$ 560,700,000
Interest rate (percent)									11.50%
Debt instrument, redemption price, percentage of principal amount redeemed		106.639%
Debt instrument, repurchased face amount		$ 403,900,000
Senior Notes \| Eldorado Notes and MTR Notes \| ERI [Member] \| Eldorado
Schedule of Equity Method Investments [Line Items]
Debt instrument, redemption price, percentage of principal amount redeemed		3.00%
Senior Notes \| New ERI Notes \| ERI [Member]
Schedule of Equity Method Investments [Line Items]
Interest rate (percent)		7.00%
Face amount of debt		$ 375,000,000.0
Term Loan \| New ERI Term Loan \| ERI [Member]
Schedule of Equity Method Investments [Line Items]
Face amount of debt		$ 425,000,000
Debt instrument, term		7 years
Debt Instrument, issue price, percentage of principal amount		99.50%
Term loan outstanding		$ 423,900,000
Debt instrument, interest rate, effective percentage								4.25%
Revolving Credit Facility \| ERI [Member]
Schedule of Equity Method Investments [Line Items]
Face amount of debt		$ 150,000,000
Debt instrument, term		5 years
Long-term line of credit		$ 40,000,000						$ 18,000,000
Line of credit facility, remaining borrowing capacity								$ 132,000,000
Debt instrument, interest rate, effective percentage								3.25%
London Interbank Offered Rate (LIBOR) \| Term Loan \| New ERI Term Loan \| ERI [Member]
Schedule of Equity Method Investments [Line Items]
Debt instrument, basis spread on variable rate		3.25%
Debt instrument, interest rate floor		1.00%
Base Rate \| Term Loan \| New ERI Term Loan \| ERI [Member]
Schedule of Equity Method Investments [Line Items]
Debt instrument, basis spread on variable rate		2.25%
Minimum \| London Interbank Offered Rate (LIBOR) \| Revolving Credit Facility \| ERI [Member]
Schedule of Equity Method Investments [Line Items]
Debt instrument, basis spread on variable rate		2.50%
Minimum \| Base Rate \| Revolving Credit Facility \| ERI [Member]
Schedule of Equity Method Investments [Line Items]
Debt instrument, basis spread on variable rate		1.50%
Maximum \| London Interbank Offered Rate (LIBOR) \| Revolving Credit Facility \| ERI [Member]
Schedule of Equity Method Investments [Line Items]
Debt instrument, basis spread on variable rate		3.25%
Maximum \| Base Rate \| Revolving Credit Facility \| ERI [Member]
Schedule of Equity Method Investments [Line Items]
Debt instrument, basis spread on variable rate		2.25%
Scenario, Forecast [Member] \| Senior Notes \| New ERI Notes \| ERI [Member]
Schedule of Equity Method Investments [Line Items]
Debt instrument, redemption price, percentage					100.00%	105.25%