Quarterly report pursuant to Section 13 or 15(d)

Employee Severance Costs (Details)

v2.4.1.9
Employee Severance Costs (Details) (USD $)
In Thousands, unless otherwise specified
9 Months Ended
Mar. 31, 2014
Mar. 31, 2015
Employee Severance, Termination Benefits [Member]    
Restructuring Cost and Reserve [Line Items]    
Restructuring Charges $ 250us-gaap_RestructuringCharges
/ us-gaap_RestructuringCostAndReserveAxis
= mpet_EmployeeSeveranceTerminationBenefitsMember
 
Discontinued Operations [Member] | Employee Severance [Member]    
Restructuring Cost and Reserve [Line Items]    
Restructuring Charges 1,500us-gaap_RestructuringCharges
/ us-gaap_IncomeStatementLocationAxis
= us-gaap_SegmentDiscontinuedOperationsMember
/ us-gaap_RestructuringCostAndReserveAxis
= us-gaap_EmployeeSeveranceMember
 
General and Administrative Expense [Member] | Employee Severance [Member]    
Restructuring Cost and Reserve [Line Items]    
Restructuring Charges   $ 475us-gaap_RestructuringCharges
/ us-gaap_IncomeStatementLocationAxis
= us-gaap_GeneralAndAdministrativeExpenseMember
/ us-gaap_RestructuringCostAndReserveAxis
= us-gaap_EmployeeSeveranceMember