XML 190 R32.htm IDEA: XBRL DOCUMENT v3.21.2

Financial Instruments - Additional Information (Detail) - USD ($) $ in Millions	Jun. 30, 2021	Dec. 31, 2020
Strategic Investment | Fair Value, Measurements, Recurring
Schedule of Available-for-sale Securities [Line Items]
Strategic investments fair value	$ 14.4	$ 10.5

X

- Definition

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

+ References

No definition available.

+ Details

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

X

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123583765&loc=SL75117539-209714

+ Details

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

X

- Details

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

X

- Details

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