Annual report pursuant to Section 13 and 15(d)

Notes Payable (Premier Trust Note) (Details)

v2.4.1.9
Notes Payable (Premier Trust Note) (Details) (USD $)
In Thousands, unless otherwise specified
0 Months Ended
Sep. 01, 2010
installment
Dec. 31, 2014
Dec. 31, 2013
Debt Instrument [Line Items]      
Note payable   $ 56,034us-gaap_NotesPayable $ 64,648us-gaap_NotesPayable
Premier Trust Note      
Debt Instrument [Line Items]      
Term 5 years    
Note payable $ 1,161us-gaap_NotesPayable
/ us-gaap_DebtInstrumentAxis
= lts_PremierTrustNoteMember
   
Stated percentage 6.50%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_DebtInstrumentAxis
= lts_PremierTrustNoteMember
   
Number of installments 20lts_DebtInstrumentNumberofInstallments
/ us-gaap_DebtInstrumentAxis
= lts_PremierTrustNoteMember
   
Frequency of periodic payment quarterly