Annual report pursuant to Section 13 and 15(d)

Subsequent Events (Details)

v2.4.1.9
Subsequent Events (Details) (USD $)
12 Months Ended 0 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Feb. 17, 2015
Feb. 23, 2015
Subsequent Event [Line Items]          
Contribution from Ascent Capital $ 0us-gaap_ProceedsFromContributionsFromParent $ 20,000,000us-gaap_ProceedsFromContributionsFromParent $ 0us-gaap_ProceedsFromContributionsFromParent    
Revolving Credit Facility Due 2017 | Revolving Credit Facility | Subsequent Event          
Subsequent Event [Line Items]          
Increase in borrowing capacity of credit line       90,000,000mtii_LineOfCreditFacilityIncreaseInMaximumBorrowingCapacity
/ us-gaap_DebtInstrumentAxis
= mtii_RevolvingCreditFacilityDue2017Member
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_RevolvingCreditFacilityMember
/ us-gaap_SubsequentEventTypeAxis
= us-gaap_SubsequentEventMember
 
LiveWatch Security, LLC | Subsequent Event          
Subsequent Event [Line Items]          
Fair value of consideration         67,000,000us-gaap_BusinessCombinationConsiderationTransferred1
/ us-gaap_BusinessAcquisitionAxis
= mtii_LiveWatchSecurityLLCMember
/ us-gaap_SubsequentEventTypeAxis
= us-gaap_SubsequentEventMember
Retention Metric | LiveWatch Security, LLC | Subsequent Event          
Subsequent Event [Line Items]          
Contingent consideration liability         6,000,000us-gaap_BusinessCombinationContingentConsiderationLiability
/ us-gaap_BusinessAcquisitionAxis
= mtii_LiveWatchSecurityLLCMember
/ us-gaap_ContingentConsiderationByTypeAxis
= mtii_ContingentConsiderationRetentionMetricMember
/ us-gaap_SubsequentEventTypeAxis
= us-gaap_SubsequentEventMember
Performance Metric | LiveWatch Security, LLC | Subsequent Event          
Subsequent Event [Line Items]          
Estimated maximum contingent consideration         8,500,000us-gaap_BusinessCombinationContingentConsiderationArrangementsRangeOfOutcomesValueHigh
/ us-gaap_BusinessAcquisitionAxis
= mtii_LiveWatchSecurityLLCMember
/ us-gaap_ContingentConsiderationByTypeAxis
= mtii_ContingentConsiderationPerformanceMetricMember
/ us-gaap_SubsequentEventTypeAxis
= us-gaap_SubsequentEventMember
Contingent consideration term         4 years
Ascent Capital | Subsequent Event          
Subsequent Event [Line Items]          
Contribution from Ascent Capital         $ 23,000,000us-gaap_ProceedsFromContributionsFromParent
/ dei_LegalEntityAxis
= mtii_AscentCapitalMember
/ us-gaap_SubsequentEventTypeAxis
= us-gaap_SubsequentEventMember