Annual report pursuant to Section 13 and 15(d)

Summary of Significant Accounting Policies (Details)

v2.4.1.9
Summary of Significant Accounting Policies (Details) (USD $)
In Thousands, unless otherwise specified
Dec. 31, 2014
Dec. 31, 2013
Related Party Transaction [Line Items]    
Money market funds $ 74,939us-gaap_MoneyMarketFundsAtCarryingValue $ 19,631us-gaap_MoneyMarketFundsAtCarryingValue
Subsidiary of Common Parent [Member]    
Related Party Transaction [Line Items]    
Ownership percentage 80.00%lts_ConsolidatedMethodInvestmentOwnershipPercentage
/ us-gaap_RelatedPartyTransactionsByRelatedPartyAxis
= us-gaap_SubsidiaryOfCommonParentMember