CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Cash flows from operating activities:
Net income	$ 4,043	$ 3,276
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	4,131	4,694
Amortization of deferred loan costs	76us-gaap_AmortizationOfFinancingCosts	76us-gaap_AmortizationOfFinancingCosts
Stock-based compensation	291us-gaap_ShareBasedCompensation	263us-gaap_ShareBasedCompensation
Provision for bad debts	7us-gaap_ProvisionForDoubtfulAccounts	29us-gaap_ProvisionForDoubtfulAccounts
Gain on disposition of assets	(18)us-gaap_GainLossOnDispositionOfAssets
Changes in operating assets and liabilities:
Receivables	152us-gaap_IncreaseDecreaseInReceivables	219us-gaap_IncreaseDecreaseInReceivables
Inventories	(8)us-gaap_IncreaseDecreaseInInventories	281us-gaap_IncreaseDecreaseInInventories
Prepaid expenses	(315)	(938)
Accounts payable	(1,674)	(1,303)
Accrued expenses	(655)	(517)
Income taxes	2,209	1,768
Net cash provided by operating activities	8,239	7,848
Cash flows from investing activities:
Proceeds from sale of assets	20
Change in construction payable	411mcri_ProceedsFromConstructionPayable	1,204mcri_ProceedsFromConstructionPayable
Acquisition of property and equipment	(7,780)	(4,960)
Net cash used in investing activities	(7,349)	(3,756)
Cash flows from financing activities:
Net exercise of stock options	297	(1,429)
Principal payments on long-term debt	(4,300)us-gaap_RepaymentsOfLongTermDebt	(4,900)us-gaap_RepaymentsOfLongTermDebt
Net cash used in financing activities	(4,003)	(6,329)
Net decrease in cash	(3,113)	(2,237)
Cash and cash equivalents at beginning of period	21,583	21,583
Cash and cash equivalents at end of period	18,470	17,093
Supplemental disclosure of cash flow information:
Cash paid for interest, net of amounts capitalized	$ 142us-gaap_InterestPaidNet	$ 242us-gaap_InterestPaidNet

Represents the cash inflow associated with construction during the period.

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Amount of noncash expense included in interest expense to issue debt and obtain financing associated with the related debt instruments. Alternate captions include noncash interest expense.

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Amount of gain (loss) on sale or disposal of property, plant and equipment assets, excluding oil and gas property and timber property.

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The increase (decrease) during the reporting period in the aggregate amount of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business.

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The amount of cash paid for interest during the period net of cash paid for interest that is capitalized.

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Amount of cash inflow (outflow) of financing activities, excluding discontinued operations. Financing activity cash flows include obtaining resources from owners and providing them with a return on, and a return of, their investment; borrowing money and repaying amounts borrowed, or settling the obligation; and obtaining and paying for other resources obtained from creditors on long-term credit.

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Amount of cash inflow (outflow) of investing activities, excluding discontinued operations. Investing activity cash flows include making and collecting loans and acquiring and disposing of debt or equity instruments and property, plant, and equipment and other productive assets.

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Amount of cash inflow (outflow) from operating activities, excluding discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities.

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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 cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets.

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The cash inflow from the sale of property, plant and equipment (capital expenditures), software, and other intangible assets.

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Amount of expense related to write-down of receivables to the amount expected to be collected. Includes, but is not limited to, accounts receivable and notes receivable.

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The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

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