XML 79 R65.htm IDEA: XBRL DOCUMENT
v3.8.0.1

EMPLOYEE BENEFIT PLANS (Detail Textuals 1) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Defined Benefit Plan Disclosure [Line Items] |  |  |
Maximum percentage of annual contribution per employee | 25.00% |  |
Percentage of employer matching contribution | 50.00% |  |
Threshold limit percentage of employee compensation | 6.00% |  |
Maximum period of vesting in contribution of employees | 3 years |  |
Employer matching contribution | $ 317,000 | $ 270,000 | $ 250,000
Stock Incentive Plan |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Number of common stock authorized to issue stock awards and options | 3,000,000 |  |
Period of stock options and restricted stock issued | 10 years |  |
Number of shares available for grants | 2,062,600 |  |
Pre-tax stock-based employee compensation expense | $ 2,682,000 | 2,624,000 | 1,993,000
After tax stock-based employee compensation expense | $ 1,729,000 | $ 1,692,000 | $ 1,285,000

X
- Definition Represents the expense recognized during the period arising from equity-based compensation arrangements before tax (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees. + References No definition available. + Details
Name: | mpx_AllocatedShareBasedCompensationExpenseBeforeTax
Namespace Prefix: | mpx_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition This element represents the threshold limit in percentage of employees' compensation. + References No definition available. + Details
Name: | mpx_DefinedContributionPlanThresholdLimitPercentageOfEmployeeCompensation
Namespace Prefix: | mpx_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition This element represents the maximum period of vesting in contribution of employees. + References No definition available. + Details
Name: | mpx_MaximumPeriodOfVestingInContributionOfEmployees
Namespace Prefix: | mpx_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Represents the term or period of stock-based compensation awards. + References No definition available. + Details
Name: | mpx_ShareBasedCompensationArrangementByShareBasedPaymentAwardPeriod
Namespace Prefix: | mpx_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition The amount of expense, net of income tax, recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees. + References No definition available. + Details
Name: | us-gaap_AllocatedShareBasedCompensationExpenseNetOfTax
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- 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 No definition available. + Details
Name: | us-gaap_DefinedBenefitPlanDisclosureLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of discretionary contributions made by an employer to a defined contribution plan. + References No definition available. + Details
Name: | us-gaap_DefinedContributionPlanEmployerDiscretionaryContributionAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan. + References No definition available. + Details
Name: | us-gaap_DefinedContributionPlanEmployerMatchingContributionPercent
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan. + References No definition available. + Details
Name: | us-gaap_DefinedContributionPlanMaximumAnnualContributionsPerEmployeePercent
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested). + 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)(3) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Details
Name: | us-gaap_PlanNameAxis=mpx_StockIncentivePlansMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |