Number of shares of equity interests issued or issuable to acquire entity.

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Percentage of voting equity interests acquired at the acquisition date in the business combination.

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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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For contingent consideration arrangements recognized in connection with a business combination, this element represents an estimate of the high-end of the potential range (undiscounted) of the consideration which may be paid.

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Face amount or stated value per share of common stock.

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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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-Glossary Investing Activities

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Business Combination (Details) (USD $) Share data in Millions, except Per Share data, unless otherwise specified	0 Months Ended
	Nov. 12, 2014	Mar. 31, 2015	Dec. 31, 2014
Business Acquisition [Line Items]
Common stock, par value (in dollars per share)		$ 0.01	$ 0.01
Future contingent payments, maximum	$ 350,000,000
Lumara Health
Business Acquisition [Line Items]
Ownership percentage acquired	100.00%
Cash consideration	600,000,000
Shares of AMAG common stock issued in business combination	3.2
Fair value of 3.2 million shares of AMAG common stock	$ 111,964,000
Lumara Health \| Common Stock
Business Acquisition [Line Items]
Common stock, par value (in dollars per share)	$ 0.01