Acquisitions - KA Medical (Details) - KA Medical $ in Millions	Nov. 06, 2020 USD ($)
Business Acquisition [Line Items]
Purchase consideration, upfront payment	$ 10.4
Purchase consideration, note payable	$ 4.0
Term of note payable	12 months

Term of note payable issued as consideration of business combination.

No definition available.

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- Definition

Amount of note payable issued by acquirer in consideration for the business combination.

+ References

No definition available.

+ Details

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Namespace Prefix:	mmsi_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- 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

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- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=120321790&loc=d3e6927-128479

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3213-108585

+ Details

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Period Type:	duration

- Details

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Period Type: