Schedule of Line of Credit Agreement With a New Secured Lender (Detail) - USD ($) $ / shares in Units, $ in Millions	6 Months Ended	9 Months Ended
Jun. 30, 2019	Sep. 30, 2019
Debt Instrument [Line Items]
Amount Due		$ 120.1
Conversion price		$ 3.00
5.75% Senior Convertible Notes
Debt Instrument [Line Items]
Amount Due	$ 18.7	$ 5.0
Annual interest rate	5.75%	5.75%
Maturity date	Oct. 31, 2021	Nov. 30, 2024
Conversion price	$ 5.15	$ 3.00
June 2020 Note
Debt Instrument [Line Items]
Amount Due		$ 2.6
Maturity date		Jun. 30, 2020
December 2020 Note
Debt Instrument [Line Items]
Amount Due		$ 2.6
Maturity date		Dec. 31, 2020
Convertible Promissory Note \| The Mann Group LLC
Debt Instrument [Line Items]
Amount Due	$ 80.6	$ 35.0
Annual interest rate	5.84%	7.00%
Maturity date	Jul. 31, 2021	Nov. 30, 2024
Conversion price	$ 4.00	$ 2.50
Non-Convertible Promissory Note \| The Mann Group LLC
Debt Instrument [Line Items]
Amount Due		$ 35.1
Annual interest rate		7.00%
Maturity date		Nov. 30, 2024
Deerfield Credit Facility \| 9.75% Credit Facility Due July 2019
Debt Instrument [Line Items]
Amount Due	$ 4.0
Annual interest rate	9.75%
Maturity date	Jul. 31, 2019
Deerfield Credit Facility \| 9.75% Credit Facility Due August 2019
Debt Instrument [Line Items]
Amount Due	$ 5.0
Annual interest rate	9.75%
Maturity date	Aug. 31, 2019
MidCap Credit Facility
Debt Instrument [Line Items]
Amount Due		$ 40.0
Maturity date		Aug. 31, 2024
MidCap Credit Facility \| LIBOR
Debt Instrument [Line Items]
Annual interest rate		6.75%
Interest rate floor		2.00%

Debt instrument floor rate.

No definition available.

Name:	mnkd_DebtInstrumentFloorRate
Namespace Prefix:	mnkd_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The price per share of the conversion feature embedded in the debt instrument.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109500613&loc=SL6031898-161870

+ Details

Name:	us-gaap_DebtInstrumentConvertibleConversionPrice1
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28551-108399

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

+ Details

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

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
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.

+ References

No definition available.

+ Details

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

- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(2))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

+ Details

Name:	us-gaap_DebtInstrumentMaturityDate
Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_DebtInstrumentAxis=mnkd_FivePointSevenFivePercentSeniorConvertibleNotesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=mnkd_JuneTwoThousandTwentyPromissoryNoteMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=mnkd_DecemberTwoThousandTwentyPromissoryNoteMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=mnkd_ConvertiblePromissoryNoteMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=mnkd_TheMannGroupLLCMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=mnkd_NonConvertiblePromissoryNoteMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=mnkd_DeerfieldCreditFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=mnkd_CreditFacilityDueJulyTwoThousandNineteenMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=mnkd_CreditFacilityDueAugustTwoThousandNineteenMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=mnkd_MidCapCreditFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableRateAxis=us-gaap_LondonInterbankOfferedRateLIBORMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: