XML 76 R44.htm IDEA: XBRL DOCUMENT
v3.10.0.1

Debt - Narrative (Details) |  |  |  | 9 Months Ended |  |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Jan. 16, 2018 USD ($) | Oct. 13, 2017 USD ($) advance | Mar. 04, 2016 USD ($) | Sep. 29, 2018 USD ($) | Dec. 30, 2017 | Nov. 15, 2017 USD ($) series | Oct. 12, 2017 USD ($) | Feb. 15, 2017 USD ($) | Dec. 08, 2016 EUR (€) series | Dec. 08, 2016 USD ($) series
Credit Agreement |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Debt term |  |  | 5 years |  |  |  |  |  |  |
Maximum borrowing capacity |  |  | $ 700,000,000 |  |  |  |  |  |  |
Additional uncommitted borrowing capacity |  | $ 300,000,000 | 150,000,000 |  |  |  |  |  |  |
Additional uncommitted borrowing capacity, minimum increments |  |  | $ 25,000,000 |  |  |  |  |  |  |
Number of advances | advance |  | 2 |  |  |  |  |  |  |  |
Effective interest rate |  |  |  | 3.49% |  |  |  |  |  |
Letter of credit oustanding |  |  |  | $ 100,000 |  |  |  |  |  |
Credit Agreement | Minimum |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Commitment fee |  |  | 0.15% |  |  |  |  |  |  |
Credit Agreement | Maximum |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Commitment fee |  |  | 0.25% |  |  |  |  |  |  |
Credit Agreement | LIBOR | Minimum |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Basis spread on variable rate |  |  | 1.00% |  |  |  |  |  |  |
Credit Agreement | LIBOR | Maximum |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Basis spread on variable rate |  |  | 2.00% |  |  |  |  |  |  |
Credit Agreement | Base Rate | Minimum |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Basis spread on variable rate |  |  | 0.00% |  |  |  |  |  |  |
Credit Agreement | Base Rate | Maximum |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Basis spread on variable rate |  |  | 1.00% |  |  |  |  |  |  |
Credit Agreement | Revolving Credit Facility |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Maximum borrowing capacity |  | $ 700,000,000 | $ 575,000,000 |  |  |  | $ 575,000,000 |  |  |
Remaining borrowing capacity |  |  |  | 699,900,000 |  |  |  |  |  |
Credit Agreement | Term Loan Credit Facility |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Maximum borrowing capacity, credit facility |  | 200,000,000 | $ 125,000,000 |  |  |  |  |  |  |
Proceeds from issuance of debt | $ 75,000,000 | $ 125,000,000 |  |  |  |  |  |  |  |
Quarterly payments, percentage of loan |  |  |  |  | 1.25% |  |  |  |  |
Periodic payment | 2,500,000 |  |  |  |  |  |  |  |  |
Repayments of debt |  |  |  | $ 35,000,000 |  |  |  |  |  |
Euro Senior Notes, Series A and B |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Face amount of debt | € |  |  |  |  |  |  |  |  | € 212,000,000 |
Number of series | series |  |  |  |  |  | 2 |  |  | 2 | 2
Euro Senior Notes, Series A due 2023 |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Face amount of debt | € |  |  |  |  |  |  |  |  | € 117,000,000 |
Stated interest rate |  |  |  |  |  |  |  |  | 1.14% | 1.14%
Euro Senior Notes, Series B due 2028 |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Face amount of debt | € |  |  |  |  |  |  |  |  | € 95,000,000 |
Stated interest rate |  |  |  |  |  |  |  |  | 1.83% | 1.83%
U.S. Senior Notes, Series A and B |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Face amount of debt |  |  |  |  |  |  |  |  |  | $ 125,000,000
U.S. Senior Notes, Series A |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Face amount of debt |  |  |  |  |  |  |  | $ 25,000,000 |  |
Stated interest rate |  |  |  |  |  |  |  | 3.03% |  |
U.S. Senior Notes, Series B |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Face amount of debt |  |  |  |  |  |  |  | $ 100,000,000 |  |
Stated interest rate |  |  |  |  |  |  |  | 3.74% |  |
US Senior Notes A and B Due 2025 and 2030 |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Face amount of debt |  |  |  |  |  | $ 175,000,000 |  |  |  |
U.S. Senior Notes, Series A due 2025 |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Face amount of debt | $ 50,000,000 |  |  |  |  |  |  |  |  |
Stated interest rate | 3.48% |  |  |  |  |  |  |  |  |
U.S. Senior Notes, Series B due 2030 |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Face amount of debt | $ 125,000,000 |  |  |  |  |  |  |  |  |
Stated interest rate | 3.78% |  |  |  |  |  |  |  |  |

X
- Definition Maximum borrowing capacity under a debt agreement on the amount that could be borrowed with a combination of, but not limited to, a line of credit and term loan. + References No definition available. + Details
Name: | lfus_DebtAgreementMaximumBorrowingCapacity
Namespace Prefix: | lfus_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The amount of quarterly payments required to be made on a debt instrument, as a percentage of the original loan. + References No definition available. + Details
Name: | lfus_DebtInstrumentQuarterlyPaymentsPercentageofLoan
Namespace Prefix: | lfus_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Additional uncommitted borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility. + References No definition available. + Details
Name: | lfus_LineofCreditFacilityAdditionalUncommittedBorrowingCapacity
Namespace Prefix: | lfus_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The minimum incremental increase to the additional uncommitted borrowing capacity under a line of credit facility. + References No definition available. + Details
Name: | lfus_LineofCreditFacilityAdditionalUncommittedBorrowingCapacityMinimumIncrements
Namespace Prefix: | lfus_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The number of advances will be made by the lender. + References No definition available. + Details
Name: | lfus_NumberofAdvances
Namespace Prefix: | lfus_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Number of Series + References No definition available. + Details
Name: | lfus_NumberofSeries
Namespace Prefix: | lfus_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Percentage points added to the reference rate to compute the variable rate on the debt instrument. + References No definition available. + Details
Name: | us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Face (par) amount of debt instrument at time of issuance. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28551-108399 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400 + Details
Name: | us-gaap_DebtInstrumentFaceAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 6 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109500613&loc=SL6036836-161870 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28551-108399 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_DebtInstrumentInterestRateEffectivePercentage
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Contractual interest rate for funds borrowed, under the debt agreement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
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_DebtInstrumentLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of the required periodic payments including both interest and principal payments. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 470 -Section 50 -Paragraph 3 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823 + Details
Name: | us-gaap_DebtInstrumentPeriodicPayment
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
Name: | us-gaap_DebtInstrumentTerm
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition The total amount of the contingent obligation under letters of credit outstanding as of the reporting date. + References No definition available. + Details
Name: | us-gaap_LettersOfCreditOutstandingAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility. + References No definition available. + Details
Name: | us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3255-108585 + Details
Name: | us-gaap_ProceedsFromIssuanceOfLongTermDebt
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3291-108585 + Details
Name: | us-gaap_RepaymentsOfLongTermDebt
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

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

X
- Details
Name: | srt_RangeAxis=srt_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_VariableRateAxis=us-gaap_LondonInterbankOfferedRateLIBORMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_VariableRateAxis=us-gaap_BaseRateMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_CreditFacilityAxis=us-gaap_RevolvingCreditFacilityMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_CreditFacilityAxis=lfus_TermLoanCreditFacilityMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

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

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

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

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

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

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=lfus_USSeniorNotesAAndBDue2025And2030Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

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