XML 38 R44.htm IDEA: XBRL DOCUMENT
v3.19.3

Investments - Additional Information (Detail) - USD ($) | 9 Months Ended |
--- | --- | ---
Sep. 28, 2019 | Dec. 29, 2018
Debt Securities, Available-for-sale [Line Items] |  |
Investments maximum maturity period | 5 years |
Unrealized gain (loss), net of unrealized gains/losses, on the investments in the bond portfolio | $ 1,505,000 | $ (1,184,000)

X
- Definition Investments maximum maturity period, years + References No definition available. + Details
Name: | lstr_InvestmentsMaximumMaturityPeriod
Namespace Prefix: | lstr_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount before tax of unrealized gain (loss) in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale. + References No definition available. + Details
Name: | us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainLossBeforeTax
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration