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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 liabilities incurred by the acquirer as part of consideration transferred 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 interests issued by the acquirer combined with noncontrolling interest.

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Mergers and Acquisitions - Fair Value of Consideration Transferred (Detail) (USD $) In Thousands, unless otherwise specified	9 Months Ended		0 Months Ended		0 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Aug. 08, 2014 Trans Ova Genetics, LC	Aug. 08, 2014 Trans Ova Genetics, LC	Mar. 06, 2014 Medistem, Inc.	Mar. 06, 2014 Medistem, Inc. Settlement of Promissory Notes
Business Acquisition [Line Items]
Cash			$ 63,165		$ 4,920
Common shares			32,802		19,368
Deferred cash consideration	20,115	0	20,115
Fair value of consideration transferred			116,082		24,995	707
Fair value of noncontrolling interest				7,437
Business combination, consideration transferred and noncontrolling interest				$ 123,519