Summary of Significant Accounting Policies - Schedule of Shares used in Calculation of Earnings Per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Accounting Policies [Abstract]
Net income attributable to Wynn Resorts, Limited	$ 572,430	$ 747,181	$ 241,975
Weighted average common shares outstanding (used in calculation of basic earnings per share)	106,529	102,071	101,445
Weighted average common and common equivalent shares outstanding (used in calculation of diluted earnings per share)	107,032	102,598	101,855
Potential dilution from the assumed exercise of stock options and nonvested stock	503	527	410
Earnings Per Share, Basic	$ 5.37	$ 7.32	$ 2.39
Earnings Per Share, Diluted	$ 5.35	$ 7.28	$ 2.38
Anti-dilutive stock options excluded from the calculation of diluted earnings per share	102	106	758