Quarterly report pursuant to Section 13 or 15(d)

Acquisitions (Narrative) (Details)

v2.4.1.9
Acquisitions (Narrative) (Details) (USD $)
3 Months Ended 0 Months Ended
Mar. 31, 2015
Mar. 31, 2014
Jan. 02, 2015
Business Acquisition [Line Items]      
Revenues $ 278,823,000us-gaap_Revenues $ 211,818,000us-gaap_Revenues  
Net income (3,572,000)us-gaap_ProfitLoss 4,264,000us-gaap_ProfitLoss  
Securities Service Network, Inc. (SSN)      
Business Acquisition [Line Items]      
Cash paid in acquisition 25,000,000us-gaap_BusinessCombinationConsiderationTransferred1
/ us-gaap_BusinessAcquisitionAxis
= lts_SecuritiesServiceNetworkInc.SSNMember
  47,287,000us-gaap_BusinessCombinationConsiderationTransferred1
/ us-gaap_BusinessAcquisitionAxis
= lts_SecuritiesServiceNetworkInc.SSNMember
Goodwill, deductible period for income tax purposes 15 years    
Revenues 28,912,000us-gaap_Revenues
/ us-gaap_BusinessAcquisitionAxis
= lts_SecuritiesServiceNetworkInc.SSNMember
   
Net income 636,000us-gaap_ProfitLoss
/ us-gaap_BusinessAcquisitionAxis
= lts_SecuritiesServiceNetworkInc.SSNMember
   
Securities Service Network, Inc. (SSN) | Promissory Notes | 0.41% Promissory Notes      
Business Acquisition [Line Items]      
Notes payable - long term     25,000,000us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesLongTermDebt
/ us-gaap_BusinessAcquisitionAxis
= lts_SecuritiesServiceNetworkInc.SSNMember
/ us-gaap_DebtInstrumentAxis
= lts_ZeroPointFourOnePercentPromissoryNotesMember
/ us-gaap_LongtermDebtTypeAxis
= lts_PromissoryNotesMember
Interest rate, stated percentage     0.41%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_BusinessAcquisitionAxis
= lts_SecuritiesServiceNetworkInc.SSNMember
/ us-gaap_DebtInstrumentAxis
= lts_ZeroPointFourOnePercentPromissoryNotesMember
/ us-gaap_LongtermDebtTypeAxis
= lts_PromissoryNotesMember
Securities Service Network, Inc. (SSN) | Promissory Notes | 1.74% Promissory Notes      
Business Acquisition [Line Items]      
Notes payable - long term     20,000,000us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesLongTermDebt
/ us-gaap_BusinessAcquisitionAxis
= lts_SecuritiesServiceNetworkInc.SSNMember
/ us-gaap_DebtInstrumentAxis
= lts_OnePointSevenFourPercentPromissoryNotesMember
/ us-gaap_LongtermDebtTypeAxis
= lts_PromissoryNotesMember
Interest rate, stated percentage     1.74%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_BusinessAcquisitionAxis
= lts_SecuritiesServiceNetworkInc.SSNMember
/ us-gaap_DebtInstrumentAxis
= lts_OnePointSevenFourPercentPromissoryNotesMember
/ us-gaap_LongtermDebtTypeAxis
= lts_PromissoryNotesMember
Debt instrument, term     4 years
Periodic payment     18,697,000us-gaap_DebtInstrumentPeriodicPayment
/ us-gaap_BusinessAcquisitionAxis
= lts_SecuritiesServiceNetworkInc.SSNMember
/ us-gaap_DebtInstrumentAxis
= lts_OnePointSevenFourPercentPromissoryNotesMember
/ us-gaap_LongtermDebtTypeAxis
= lts_PromissoryNotesMember
Imputed interest rate     5.10%lts_DebtInstrumentImputedInterestRate
/ us-gaap_BusinessAcquisitionAxis
= lts_SecuritiesServiceNetworkInc.SSNMember
/ us-gaap_DebtInstrumentAxis
= lts_OnePointSevenFourPercentPromissoryNotesMember
/ us-gaap_LongtermDebtTypeAxis
= lts_PromissoryNotesMember
Amount to be paid in excess of net worth of promissory notes     3,590lts_AmounttobePaidinExcessofNetWorthofPromissoryNotes
/ us-gaap_BusinessAcquisitionAxis
= lts_SecuritiesServiceNetworkInc.SSNMember
/ us-gaap_DebtInstrumentAxis
= lts_OnePointSevenFourPercentPromissoryNotesMember
/ us-gaap_LongtermDebtTypeAxis
= lts_PromissoryNotesMember
KMS Financial Services, Inc. and Securities Service Network, Inc. (SSN)      
Business Acquisition [Line Items]      
Non-recurring income tax benefit eliminated from the pro forma results $ 21,238,000lts_IncomeTaxExpenseBenefitEliminatedfromProFormaResults
/ us-gaap_BusinessAcquisitionAxis
= lts_KMSFinancialServicesInc.andSecuritiesServiceNetworkInc.SSNMember