Amount due from sellers in business combination.

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Amount of consideration paid at closing for a business combination.

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Amount of working capital adjustment associatd with the acquisition of business.

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Amount of restricted cash acquired in a business combination.

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.

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Amount of liability recognized arising from contingent consideration in a business combination.

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Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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- Definition

Amount due from customers or clients for goods or services, including trade receivables, that have been delivered or sold in the normal course of business, and amounts due from others, including related parties expected to be converted to cash, sold or exchanged within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount of liabilities incurred for goods and services received that are used in an entity's business and related party payables, assumed at the acquisition date.

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Amount of other liabilities due within one year or within the normal operating cycle, if longer, assumed at the acquisition date.

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Amount of deferred tax asset attributable to deductible temporary differences and carryforwards that are expected to be realized or consumed after one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount of deferred tax liability attributable to taxable temporary differences due after one year or the normal operating cycle, if longer, assumed at the acquisition date.

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Amount of assets, excluding financial assets and goodwill, that lack physical substance, having a projected indefinite period of benefit, acquired at the acquisition date.

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The amount of identifiable intangible assets recognized as of the acquisition date.

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The amount of inventory recognized as of the acquisition date.

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Amount recognized as of the acquisition date for the identifiable assets acquired in excess of (less than) the aggregate liabilities assumed.

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Amount of other liabilities due after one year or the normal operating cycle, if longer, assumed at the acquisition date.

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Amount of other assets expected to be realized or consumed after one year or the normal operating cycle, if longer, acquired at the acquisition date.

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- Definition

The amount of property, plant, and equipment recognized as of the acquisition date.

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Amount recognized for assets, including goodwill, in excess of (less than) the aggregate liabilities assumed.

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The cash inflow associated with the acquisition of business during the period (for example, cash that was held by the acquired business).

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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Business Combination (Details 2) (USD $) In Thousands, unless otherwise specified	0 Months Ended
	Nov. 12, 2014	Mar. 31, 2015	Dec. 31, 2014
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net [Abstract]
Goodwill		$ 205,824us-gaap_Goodwill	$ 205,824us-gaap_Goodwill
Lumara Health
Business Acquisition [Line Items]
Cash consideration	600,000
Fair value of 3.2 million shares of AMAG common stock	111,964
Fair value of contingent milestone payments	205,000
Estimated working capital and other adjustments	821
Purchase price paid at closing	917,785
Due from sellers	(5,119)
Cash acquired from Lumara Health	(5,219)
Total purchase price paid	907,447
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net [Abstract]
Accounts receivable	34,918
Inventories	30,300
Prepaid and other current assets	3,322
Deferred income tax liabilities	94,965
Property and equipment	60
Makena marketed product	797,100
IPR & D	79,100
Restricted cash	1,997
Other long-term assets	3,412
Accounts payable	(3,807)
Accrued expenses	(41,532)
Deferred income tax liabilities	(293,649)
Other long-term liabilities	(4,563)
Total estimated identifiable net assets	701,623
Goodwill	205,824		205,800
Total	$ 907,447