XML 91 R72.htm IDEA: XBRL DOCUMENT
v3.20.4

Fair Value of Assets and Liabilities - Carrying Value and Estimated Fair Value of Senior Notes (Details) - Senior Notes - USD ($) $ in Thousands | Dec. 26, 2020 | Dec. 28, 2019
--- | --- | ---
Carrying Value | Euro Senior Notes, Series A due 2023 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions |  |
Long-term debt fair value | $ 142,679 | $ 129,808
Carrying Value | Euro Senior Notes, Series B due 2028 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions |  |
Long-term debt fair value | 115,850 | 105,400
Carrying Value | USD Senior Notes, Series A due 2022 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions |  |
Long-term debt fair value | 25,000 | 25,000
Carrying Value | USD Senior Notes, Series B due 2027 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions |  |
Long-term debt fair value | 100,000 | 100,000
Carrying Value | USD Senior Notes, Series A due 2025 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions |  |
Long-term debt fair value | 50,000 | 50,000
Carrying Value | USD Senior Notes, Series B due 2030 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions |  |
Long-term debt fair value | 125,000 | 125,000
Estimated Fair Value | Euro Senior Notes, Series A due 2023 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions |  |
Long-term debt fair value | 144,323 | 131,710
Estimated Fair Value | Euro Senior Notes, Series B due 2028 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions |  |
Long-term debt fair value | 123,588 | 110,336
Estimated Fair Value | USD Senior Notes, Series A due 2022 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions |  |
Long-term debt fair value | 25,437 | 25,054
Estimated Fair Value | USD Senior Notes, Series B due 2027 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions |  |
Long-term debt fair value | 109,552 | 102,548
Estimated Fair Value | USD Senior Notes, Series A due 2025 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions |  |
Long-term debt fair value | 53,474 | 50,775
Estimated Fair Value | USD Senior Notes, Series B due 2030 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions |  |
Long-term debt fair value | $ 138,036 | $ 127,701

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_FairValueBalanceSheetGroupingFinancialStatementCaptionsLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. + References No definition available. + Details
Name: | us-gaap_LongTermDebtFairValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Details
Name: | us-gaap_FairValueByMeasurementBasisAxis=us-gaap_CarryingReportedAmountFairValueDisclosureMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=us-gaap_SeniorNotesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=lfus_EuroSeniorNotesSeriesAMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=lfus_EuroSeniorNotesSeriesBMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=lfus_USSeniorNotesSeriesADue2022Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=lfus_USSeniorNotesSeriesBDue2027Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=lfus_USSeniorNotesSeriesADue2025Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=lfus_USSeniorNotesSeriesBDue2030Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByMeasurementBasisAxis=us-gaap_EstimateOfFairValueFairValueDisclosureMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |