Name:	amag_PaymentForExerciseOfOptionToAcquireGlobalRightsToDifProgram
Namespace Prefix:	amag_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Represents the payments due for sales milestones based upon the achievement of annual sales milestones.

No definition available.

Name:	amag_SalesMilestonePaymentsBasedOnAchievementOfAnnualSalesMilestones
Namespace Prefix:	amag_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Represents the annual sales milestone targets that will require additional payments.

No definition available.

Name:	amag_SalesMilestoneTargets
Namespace Prefix:	amag_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Upfront payment made for the option to acquire the global rights to the DIF program.

No definition available.

Name:	amag_UpfrontPaymentIssuedForOptionAgreement
Namespace Prefix:	amag_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

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.

No definition available.

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

Total costs related to goods produced and sold during the reporting period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.2(a))
-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688