Note 8 - Stockholders' Equity (Details Textual) - USD ($) $ / shares in Units, $ in Thousands		9 Months Ended
Jun. 12, 2020	Dec. 31, 2020	Dec. 31, 2019
Stock Issued During Period, Shares, New Issues (in shares)	600,000	600,000
Sale of Stock, Underwriter Options, Shares (in shares)	90,000
Shares Issued, Price Per Share (in dollars per share)	$ 225.00
Proceeds from Issuance of Common Stock	$ 145,935	$ 145,935	$ 84,995
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Cumulative Effect of Adjustment, Vested in Period		1,629
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Cumulative Effect of Adjustment, Vested in Period, Net of Tax		$ 1,209
Share Based Compensation Effect on Earning per Share Basic (in dollars per share)		$ 0.25
Share-based Payment Arrangement, Expected Noncash Expense, Increased (Decrease) Per Quarter		$ 194
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)		1 year

The number of shares that can be granted upon exercise of underwriter options.

No definition available.

Name:	mlab_SaleOfStockUnderwriterOptionsShares
Namespace Prefix:	mlab_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the impact of share-based compensation in basic earning per share computations.

+ References

No definition available.

+ Details

Name:	mlab_ShareBasedCompensationEffectOnEarningPerShareBasic
Namespace Prefix:	mlab_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the cumulative effect of adjustment for share based compensation for equity instrument other than option.

+ References

No definition available.

+ Details

Name:	mlab_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsCumulativeEffectOfAdjustmentVestedInPeriod
Namespace Prefix:	mlab_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Represents the cumulative effect of adjustment for share based compensation for equity instrument other than option net of tax.

+ References

No definition available.

+ Details

Name:	mlab_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsCumulativeEffectOfAdjustmentVestedInPeriodNetOfTax
Namespace Prefix:	mlab_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Represents the expected increase (decrease) non-cash share based compensation expense during each quarter.

+ References

No definition available.

+ Details

Name:	mlab_SharebasedPaymentArrangementExpectedNoncashExpenseIncreasedDecreasePerQuarter
Namespace Prefix:	mlab_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The cash inflow from the additional capital contribution to the entity.

+ 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 (a)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3255-108585

+ Details

Name:	us-gaap_ProceedsFromIssuanceOfCommonStock
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Per share or per unit amount of equity securities issued.

+ References

No definition available.

+ Details

Name:	us-gaap_SharesIssuedPricePerShare
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Number of new stock issued during the period.

+ 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(29))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21463-112644

Reference 3: 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=120397183&loc=d3e187085-122770

Reference 4: 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(28))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

Name:	us-gaap_StockIssuedDuringPeriodSharesNewIssues
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_AwardTypeAxis=us-gaap_RestrictedStockUnitsRSUMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: