XML 28 R72.htm IDEA: XBRL DOCUMENT
v3.19.3.a.u2

Debt - Narrative (Details) |  | 12 Months Ended |
--- | --- | --- | ---
Mar. 09, 2017 $ / shares | Dec. 28, 2019 USD ($) | Dec. 29, 2018 USD ($) | Dec. 30, 2017 USD ($) | Dec. 28, 2019 KRW (₩)
Debt Instrument [Line Items] |  |  |  |  |
Cash dividend (in dollars per share) | $ / shares | $ 3.00 |  |  |  |
Cash dividend, subordinated debentures (in dollars per share) | $ / shares | $ 5.00 |  |  |  |
Interest paid |  | $ 25,400,000 | $ 25,200,000 | $ 13,800,000 |
Subordinated Debt [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt, stated interest rate |  | 6.00% |  |  | 6.00%
Debt instrument, call feature, period, latest |  | 5 years |  |  |
Revolving Credit Facility [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Line of credit facility, current borrowing capacity |  | $ 350,000,000.0 |  |  |
Credit Agreement [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Outstanding letters of credit |  | 11,900,000 |  |  |
Jungwoo-Mueller [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Line of credit facility maximum borrowing capacity |  | $ 21,900,000 |  |  | ₩ 25,800,000,000
Minimum [Member] | Credit Agreement [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Credit facility commitment fee |  | 0.15% |  |  |
Maximum [Member] | Credit Agreement [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Credit facility commitment fee |  | 0.30% |  |  |
LIBOR [Member] | Credit Agreement [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Basis spread on variable rate |  | 1.50% |  |  |
LIBOR [Member] | Minimum [Member] | Credit Agreement [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Basis spread on variable rate |  | 1.125% |  |  |
LIBOR [Member] | Maximum [Member] | Credit Agreement [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Basis spread on variable rate |  | 1.625% |  |  |
Base Rate [Member] | Credit Agreement [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Basis spread on variable rate |  | 0.50% |  |  |
Base Rate [Member] | Minimum [Member] | Credit Agreement [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Basis spread on variable rate |  | 0.125% |  |  |
Base Rate [Member] | Maximum [Member] | Credit Agreement [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Basis spread on variable rate |  | 0.625% |  |  |

X
- Definition Amount of paid and unpaid paid-in-kind dividends (PIK) in debentures. + References No definition available. + Details
Name: | mli_CommonStockDividendsPerSharePaidInKind
Namespace Prefix: | mli_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | duration

X
- Definition Debt Instrument, Call Feature, Period, Latest + References No definition available. + Details
Name: | mli_DebtInstrumentCallFeaturePeriodLatest
Namespace Prefix: | mli_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Aggregate dividends paid during the period for each share of common stock outstanding. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 + Details
Name: | us-gaap_CommonStockDividendsPerShareCashPaid
Namespace Prefix: | us-gaap_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | duration

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 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 cash paid for interest, excluding capitalized interest, classified as operating activity. Includes, but is not limited to, payment to settle zero-coupon bond for accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4297-108586 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 17 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3367-108585 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 25 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3536-108585 + Details
Name: | us-gaap_InterestPaidNet
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
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 The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used. + References No definition available. + Details
Name: | us-gaap_LineOfCreditFacilityCommitmentFeePercentage
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any 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_LineOfCreditFacilityCurrentBorrowingCapacity
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
- Details
Name: | us-gaap_LongtermDebtTypeAxis=us-gaap_SubordinatedDebtMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LineOfCreditFacilityAxis=us-gaap_LineOfCreditMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LineOfCreditFacilityAxis=mli_CreditAgreementMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LineOfCreditFacilityAxis=mli_JungwooMuellerMember
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: |