Note 2 - Acquisitions and Dispositions - Pro Forma Effects (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Infitrak Acquisition [Member]
Revenues	$ 21,858	$ 19,302	$ 41,774	$ 36,465
Net income	$ 1,765	$ 3,150	$ 4,360	$ 5,122
Net Income per common share:
Basic (in dollars per share)	$ 0.49	$ 0.90	$ 1.22	$ 1.46
Diluted (in dollars per share)	$ 0.47	$ 0.87	$ 1.17	$ 1.40
Revenues	$ 21,858	$ 19,302	$ 41,774	$ 36,465
Net income	1,765	3,150	4,360	5,122
North Bay Acquisition [Member]
Revenues	22,124	19,620	41,328	37,100
Net income	$ 1,826	$ 3,210	$ 4,352	$ 5,241
Net Income per common share:
Basic (in dollars per share)	$ 0.51	$ 0.91	$ 1.21	$ 1.50
Diluted (in dollars per share)	$ 0.49	$ 0.88	$ 1.17	$ 1.44
Revenues	$ 22,124	$ 19,620	$ 41,328	$ 37,100
Net income	$ 1,826	$ 3,210	$ 4,352	$ 5,241

The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (h)(2)-(3)

-URI http://asc.fasb.org/extlink&oid=56956515&loc=d3e1392-128463

+ Details

Name:	us-gaap_BusinessAcquisitionProFormaEarningsPerShareBasic
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

- Definition

The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

+ References

+ Details

Name:	us-gaap_BusinessAcquisitionProFormaEarningsPerShareDiluted
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

- References

No definition available.

+ Details

Name:	us-gaap_BusinessAcquisitionProFormaInformationAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

+ References

+ Details

Name:	us-gaap_BusinessAcquisitionsProFormaNetIncomeLoss
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

+ References

+ Details

Name:	us-gaap_BusinessAcquisitionsProFormaRevenue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

Name:	us-gaap_BusinessAcquisitionAxis=mlab_InfitrakAcquisitionMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_BusinessAcquisitionAxis=mlab_NorthBayAcquisitionMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: