CONSOLIDATED STATEMENTS OF INCOME (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Revenues
Casino	$ 145,134us-gaap_CasinoRevenue	$ 149,916us-gaap_CasinoRevenue	$ 128,831us-gaap_CasinoRevenue
Food and beverage	52,314us-gaap_FoodAndBeverageRevenue	49,642us-gaap_FoodAndBeverageRevenue	45,966us-gaap_FoodAndBeverageRevenue
Hotel	21,733us-gaap_OccupancyRevenue	22,679us-gaap_OccupancyRevenue	20,200us-gaap_OccupancyRevenue
Other	10,394us-gaap_OtherHotelOperatingRevenue	9,680us-gaap_OtherHotelOperatingRevenue	8,994us-gaap_OtherHotelOperatingRevenue
Gross revenues	229,575	231,917	203,991
Less promotional allowances	(41,808)us-gaap_PromotionalAllowances	(43,168)us-gaap_PromotionalAllowances	(40,689)us-gaap_PromotionalAllowances
Net revenues	187,767us-gaap_RevenueFromLeasedAndOwnedHotels	188,749us-gaap_RevenueFromLeasedAndOwnedHotels	163,302us-gaap_RevenueFromLeasedAndOwnedHotels
Operating expenses
Casino	61,583us-gaap_CasinoExpenses	59,646us-gaap_CasinoExpenses	53,331us-gaap_CasinoExpenses
Food and beverage	21,410us-gaap_FoodAndBeverageCostOfSales	20,077us-gaap_FoodAndBeverageCostOfSales	18,487us-gaap_FoodAndBeverageCostOfSales
Hotel	5,992us-gaap_OccupancyCosts	6,241us-gaap_OccupancyCosts	5,578us-gaap_OccupancyCosts
Other	3,545us-gaap_OtherDirectCostsOfHotels	3,260us-gaap_OtherDirectCostsOfHotels	3,001us-gaap_OtherDirectCostsOfHotels
Selling, general and administrative	52,987	52,256	48,120
Depreciation and amortization	17,824	16,638	16,651
Loss (gain) on disposition of assets	343	176	(5)
Colorado ballot initiative costs	1,864mcri_BallotInitiativeCosts
Acquisition expenses			2,156
Total operating expenses	165,548us-gaap_CostsAndExpenses	158,294us-gaap_CostsAndExpenses	147,319us-gaap_CostsAndExpenses
Income from operations	22,219us-gaap_OperatingIncomeLoss	30,455us-gaap_OperatingIncomeLoss	15,983us-gaap_OperatingIncomeLoss
Other expenses
Interest expense, net of amounts capitalized	(1,104)us-gaap_InterestExpense	(1,860)us-gaap_InterestExpense	(2,024)us-gaap_InterestExpense
Total other expenses	(1,104)us-gaap_NonoperatingIncomeExpense	(1,860)us-gaap_NonoperatingIncomeExpense	(2,024)us-gaap_NonoperatingIncomeExpense
Income before income taxes	21,115	28,595	13,959
Provision for income taxes	(6,930)us-gaap_IncomeTaxExpenseBenefit	(10,634)us-gaap_IncomeTaxExpenseBenefit	(5,048)us-gaap_IncomeTaxExpenseBenefit
Net income	$ 14,185	$ 17,961	$ 8,911
Net income
Basic (in dollars per share)	$ 0.85us-gaap_EarningsPerShareBasic	$ 1.10us-gaap_EarningsPerShareBasic	$ 0.55us-gaap_EarningsPerShareBasic
Diluted (in dollars per share)	$ 0.83us-gaap_EarningsPerShareDiluted	$ 1.06us-gaap_EarningsPerShareDiluted	$ 0.55us-gaap_EarningsPerShareDiluted
Weighted average number of common shares and potential common shares outstanding
Basic (in shares)	16,734	16,302	16,140
Diluted (in shares)	17,107	16,944	16,250

Represents expenses related to the campaign against the proposed ballot initiatives.

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Amount of gain (loss) on sale or disposal of casino gaming machines and other operational assets previously recorded in selling general and administrative expense.

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The element represents the aggregate revenue generated from managing and operating hotels during the period by the reporting entity before deducting promotional allowances, returns and discounts.

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This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

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This element represents the cost of generating revenues from a hotel's, including cruise lines, gaming operations; likewise, such revenues may be derived from gaming operations that also are hoteliers.

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Revenues generated by casino operations. Also includes revenues generated by and derived from a hotel's, including cruise lines, gaming operations; likewise, such revenues may be derived from gaming operations that also are hoteliers.

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Total costs of sales and operating expenses for the period.

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The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

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The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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The cost related to generating revenue from the sale of food (prepared and cooked-to-order foodstuffs, as well as snack items) and beverages (bottled or on-tap alcoholic beverages, as well as nonalcoholic beverages like carbonated drinks, juices, energy/sports drinks, water, coffee, and tea).

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Revenue from sale of food (prepared and cooked-to-order foodstuffs, as well as snack items) and beverages (bottled or on-tap alcoholic beverages, as well as nonalcoholic beverages like carbonated drinks, juices, energy/sports drinks, water, coffee, and tea).

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Sum of operating profit and nonoperating income or expense before Income or Loss from equity method investments, income taxes, extraordinary items, and noncontrolling interest.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount of the cost of borrowed funds accounted for as interest expense.

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Net income after adjustments for dividends on preferred stock (declared in the period) and/or cumulative preferred stock (accumulated for the period).

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The aggregate amount of income or expense from ancillary business-related activities (that is to say, excluding major activities considered part of the normal operations of the business).

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Costs incurred and are directly related to generating occupancy revenues.

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Revenue derived from the provision of short term lodging; it does not apply to lease or rental income. Includes hotel rooms, cruise revenue, and other revenue related to lodgings.

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The net result for the period of deducting operating expenses from operating revenues.

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No definition available.

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Other costs incurred and are directly related to hotel operations.

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Other revenue generated from managing and operating hotels, not otherwise defined in the taxonomy.

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This element represents the estimated retail value of accommodations, food and beverage, and other services furnished to guests without charge.

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Amount, net of promotional allowances, of revenue from managing and operating hotels, including, but not limited to, revenue from occupancy, casino, food and beverage, and retail. Excludes operating lease income.

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The aggregate total costs related to selling a firm's product and services, as well as all other general and administrative expenses. Direct selling expenses (for example, credit, warranty, and advertising) are expenses that can be directly linked to the sale of specific products. Indirect selling expenses are expenses that cannot be directly linked to the sale of specific products, for example telephone expenses, Internet, and postal charges. General and administrative expenses include salaries of non-sales personnel, rent, utilities, communication, etc.

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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

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