Benefit Plans - Defined Contribution Plan (Detail) - United States - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Defined Contribution Plan Disclosure
Company's matching contribution percentage	50.00%
Defined Contribution Plan, Cost	$ 6.4	$ 6.1	$ 6.1
Maximum
Defined Contribution Plan Disclosure
Employee contributions, percentage	6.00%
Wynn Macau
Defined Contribution Plan Disclosure
Defined Contribution Plan, Cost	$ 16.6	$ 15.8	$ 12.9
Employee contribution percentage	5.00%
Annual vesting percentage	10.00%
Vesting period	10 years

Amount of cost for defined contribution plan.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 70
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942

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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

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- Definition

Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

+ References

No definition available.

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- Definition

Percentage employer matches of the employee's percentage contribution matched.

+ References

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- Definition

Percentage of employer's matching contributions to a defined contribution plan that vests in a given year.

+ References

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- Definition

Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan.

+ References

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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