REVENUE RECOGNITION - Casino Revenue (Details) - 12 months ended Dec. 31, 2019	Total	USD ($)
CONSOLIDATED STATEMENTS OF INCOME
Number of components, progressive jackpot provisions	2	2

The number of components for progressive jackpot provisions recognized.

No definition available.

Name:	mcri_NumberOfComponentsProgressiveJackpotProvisions
Namespace Prefix:	mcri_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration