Line Of Credit Facility, Accordion Feature, Increase Limit

No definition available.

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Namespace Prefix:	masi_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

+ Details

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Period Type:	instant

- 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.

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+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

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Balance Type:	debit
Period Type:	instant

- Definition

Amount of the cost of borrowed funds accounted for as interest expense for debt.

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+ Details

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

- 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

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
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Period Type:	duration

Debt - Narrative (Details)			1 Months Ended	3 Months Ended		9 Months Ended
Debt - Narrative (Details)	Feb. 28, 2023 USD ($)	Apr. 11, 2022 USD ($)	Mar. 31, 2020 USD ($)	Sep. 30, 2023 USD ($)	Oct. 01, 2022 USD ($)	Sep. 30, 2023 USD ($)	Oct. 01, 2022 USD ($)	Feb. 28, 2023 JPY (¥)	May 16, 2022 USD ($)	May 31, 2021 USD ($)	May 31, 2021 JPY (¥)	Apr. 30, 2021 USD ($)	Apr. 30, 2021 JPY (¥)	Jun. 30, 2020 USD ($)	Jun. 30, 2020 JPY (¥)	Mar. 31, 2020 JPY (¥)
New Credit Facility Agreement
Debt Instrument [Line Items]
Accordion feature, increase limit		$ 400,000,000
New Credit Facility Agreement \| Adjusted Secured Overnight Financing Rate (SOFR)
Debt Instrument [Line Items]
Variable rate		1.00%
New Credit Facility Agreement \| Fed Funds Effective Rate Overnight Index Swap Rate
Debt Instrument [Line Items]
Variable rate		0.50%
New Credit Facility Agreement \| Adjusted Secured Overnight Financing Rate (SOFR), One-Month Interest Period
Debt Instrument [Line Items]
Variable rate		0.10%
New Credit Facility Agreement \| Adjusted Secured Overnight Financing Rate (SOFR), Three-Month Interest Period
Debt Instrument [Line Items]
Variable rate		0.15%
New Credit Facility Agreement \| Adjusted Secured Overnight Financing Rate (SOFR), Six-Month Interest Period
Debt Instrument [Line Items]
Variable rate		0.25%
New Credit Facility Agreement \| Minimum
Debt Instrument [Line Items]
Commitment fee percentage		0.15%
New Credit Facility Agreement \| Minimum \| Alternate Base Rate
Debt Instrument [Line Items]
Variable rate		0.00%
New Credit Facility Agreement \| Minimum \| Adjusted Secured Overnight Financing Rate (SOFR)
Debt Instrument [Line Items]
Variable rate		1.00%
New Credit Facility Agreement \| Maximum
Debt Instrument [Line Items]
Commitment fee percentage		0.275%
New Credit Facility Agreement \| Maximum \| Alternate Base Rate
Debt Instrument [Line Items]
Variable rate		0.75%
New Credit Facility Agreement \| Maximum \| Adjusted Secured Overnight Financing Rate (SOFR)
Debt Instrument [Line Items]
Variable rate		1.75%
Japanese Government Loans
Debt Instrument [Line Items]
Debt instrument face amount														$ 9,900,000	¥ 1,480,000,000
Average interest rate														1.33%	1.33%
Japanese Equipment Loans
Debt Instrument [Line Items]
Debt instrument face amount										$ 500,000	¥ 80,000,000	$ 1,000,000	¥ 150,000,000
Average interest rate										1.20%	1.20%	0.58%	0.58%
Revolving Credit Facility
Debt Instrument [Line Items]
Interest expense				$ 12,100,000	$ 9,000,000	$ 34,100,000	$ 13,000,000
Revolving Credit Facility \| New Credit Facility Agreement
Debt Instrument [Line Items]
Maximum borrowing capacity		$ 500,000,000							$ 705,000,000
Accordion feature, increase limit									$ 205,000,000
Revolving Credit Facility \| Line of Credit \| Japanese Revolving Loan
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 20,100,000		$ 5,400,000					¥ 3,000,000,000								¥ 800,000,000
Debt issuance costs	$ 200,000		$ 100,000					¥ 22,000,000								¥ 7,200,000
Variable rate	0.75%		0.50%
Revolving Credit Facility \| Line of Credit \| Initial Lenders
Debt Instrument [Line Items]
Debt issuance costs		8,400,000
Unsecured Debt \| New Credit Facility Agreement
Debt Instrument [Line Items]
Maximum borrowing capacity		300,000,000
Letter of Credit \| New Credit Facility Agreement
Debt Instrument [Line Items]
Maximum borrowing capacity		$ 50,000,000