Schedule of cash, cash equivalents and available-for-sale securities.

No definition available.

Name:	bmrn_ScheduleOfCashCashEquivalentsAndAvailableForSaleSecuritiesLineItems
Namespace Prefix:	bmrn_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of investment in equity security without readily determinable fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 321
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479536/321-10-50-3

+ Details

Name:	us-gaap_EquitySecuritiesWithoutReadilyDeterminableFairValueAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of loss from downward price adjustment on investment in equity security without readily determinable fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 321
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479536/321-10-50-3

+ Details

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

- Definition

Amount of impairment loss on investment in equity security without readily determinable fair value.

+ References

+ Details

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

- Details

Name:	us-gaap_FairValueByAssetClassAxis=bmrn_StrategicInvestmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FairValueByMeasurementFrequencyAxis=us-gaap_FairValueMeasurementsRecurringMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FairValueByMeasurementFrequencyAxis=us-gaap_FairValueMeasurementsNonrecurringMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

FINANCIAL INSTRUMENTS - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
	Jun. 30, 2024	Mar. 31, 2023	Dec. 31, 2023
Schedule of Available-for-sale Securities [Line Items]
Equity investment impairment amount		$ 12.6
Strategic Investment \| Fair Value, Measurements, Recurring
Schedule of Available-for-sale Securities [Line Items]
Strategic investments fair value	$ 6.7		$ 11.3
Strategic Investment \| Fair Value, Nonrecurring
Schedule of Available-for-sale Securities [Line Items]
Equity securities decline amount	$ 4.5