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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Balance Type:	na
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- Definition

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.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Percentage of principal amount of debt redeemed.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Payment Default Classification Period For Interest Payment

+ References

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+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Percentage Of Principal Repayment On Event Of Change Of Control

+ References

No definition available.

+ Details

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Namespace Prefix:	wynn_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Details

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- Details

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Long-Term Debt Long-Term Debt - 5 1/2% Senior Notes due 2025 (Details) - USD ($) $ in Millions		12 Months Ended
	Feb. 18, 2015	Dec. 31, 2018	Mar. 31, 2018
5 1/2% Senior Notes, Due March 1, 2025 \| Maximum
Debt Instrument [Line Items]
Debt redemption price as percentage of principal	100.00%	100.00%
Percentage of principal repayment on the event of change of control	101.00%
Payment default classification period for interest payment		30 days
Wynn Las Vegas, LLC and Wynn Las Vegas Capital Corp \| Senior Notes \| 5 1/2% Senior Notes, Due March 1, 2025
Debt Instrument [Line Items]
Debt instrument, interest rate		5.50%
Principal amount purchased			$ 20
Wynn Las Vegas, LLC and Wynn Las Vegas Capital Corp \| First Mortgage Notes \| 5 3/8% Wynn Las Vegas First Mortgage Notes, Due March 15, 2022
Debt Instrument [Line Items]
Debt instrument, interest rate	5.50%
Debt instrument, aggregate principal amount	$ 1,800