v2.4.0.8

Subsequent Events - Additional Information (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	1 Months Ended	9 Months Ended		12 Months Ended			1 Months Ended			0 Months Ended	1 Months Ended		12 Months Ended	9 Months Ended	0 Months Ended	1 Months Ended		0 Months Ended		4 Months Ended	1 Months Ended		0 Months Ended	1 Months Ended		2 Months Ended		0 Months Ended	1 Months Ended		0 Months Ended
	Jul. 26, 2013	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012	Dec. 31, 2011	Aug. 13, 2013	Jan. 20, 2012 Ziopharm [Member]	Feb. 07, 2011 Ziopharm [Member]	Jan. 06, 2011 Ziopharm [Member]	Mar. 15, 2013 AquaBounty [Member]	Feb. 28, 2013 AquaBounty [Member]	Jan. 31, 2013 AquaBounty [Member]	Dec. 31, 2012 AquaBounty [Member]	Sep. 30, 2013 Series F Redeemable Convertible Preferred Stock [Member]	Feb. 14, 2013 AquaBounty ECC [Member]	Mar. 31, 2013 AmpliPhi ECC [Member] Upfront and Milestone Payments [Member] Upfront [Member]	Mar. 31, 2013 Genopaver ECC [Member] Upfront and Milestone Payments [Member] Upfront [Member]	Apr. 27, 2013 Soligenix ECC [Member] Upfront and Milestone Payments [Member] Upfront [Member]	Jul. 26, 2013 Subsequent Event [Member]	Apr. 30, 2013 Subsequent Event [Member]	Oct. 31, 2013 Subsequent Event [Member] Fibrocell Science [Member]	Oct. 29, 2013 Subsequent Event [Member] Ziopharm [Member]	Mar. 15, 2013 Subsequent Event [Member] AquaBounty [Member]	Feb. 28, 2013 Subsequent Event [Member] AquaBounty [Member]	Jan. 31, 2013 Subsequent Event [Member] AquaBounty [Member]	Apr. 30, 2013 Subsequent Event [Member] Series F Redeemable Convertible Preferred Stock [Member]	Apr. 30, 2013 Subsequent Event [Member] Series F Redeemable Convertible Preferred Stock [Member] Shareholder	Feb. 14, 2013 Subsequent Event [Member] AquaBounty ECC [Member]	Mar. 31, 2013 Subsequent Event [Member] AmpliPhi ECC [Member] Upfront and Milestone Payments [Member] Upfront [Member]	Mar. 31, 2013 Subsequent Event [Member] Genopaver ECC [Member] Upfront and Milestone Payments [Member] Upfront [Member]	Apr. 27, 2013 Subsequent Event [Member] Soligenix ECC [Member] Upfront and Milestone Payments [Member] Upfront [Member]
Subsequent Event [Line Items]
Amount drawn on promissory note		$ 300		$ 200							$ 100	$ 200	$ 200											$ 100	$ 200
Royalty rate as a percentage of gross profit															16.66%													16.66%
Proceeds from issuance of redeemable convertible preferred shares														150,000												150,000
Payment of stock issuance costs		3,148	11	16	2,675																					3,100	1,800
Redeemable convertible preferred stock, stated value																										$ 7.88
Dividend rate per annum																										6.00%
Common stock, authorized		200,000,000		160,000,000	155,000,000	200,000,000														185,000,000
Number of shares acquired										18,714,814													18,714,814
Amount from private subscription offering										4,907													4,907
Aggregate percentage of ownership										53.82%													53.82%
Promissory note repaid		500	34	34	300					500													500
Collaborative arrangement consideration received, shares																24,000,000		1,034,483											24,000,000		1,034,483
Collaborative arrangement consideration received, value																2,400	3,000	1,331												3,000
Decrease In Equity Securities																				$ (32,123)
Shareholders approved a reverse stock split description	1-for-1.75																		1-for-1.75
Shares of common stock purchased from collaborative partners							1,923,075	1,910,000	2,426,235												2,439,024	2,857,143
Price per share							$ 5.20	$ 5.75	$ 4.80												$ 4.10	$ 3.50

X

- Definition

Percentage of voting equity interests acquired in a business combination achieved in stages, including equity interests in the acquiree held by the acquirer immediately before the acquisition date and acquired at the acquisition date.

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- Definition

The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

+ References

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-Publisher FASB

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-SubTopic 10

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The cash outflow for a loan, supported by a promissory note, granted to related parties where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth.

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The cash outflow for cost incurred directly with the issuance of an equity security.

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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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The cash inflow from issuance of preferred stocks identified as being convertible into another form of financial instrument, typically the entity's common stock.

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The cash inflow from a loan, supported by a promissory note, granted to related parties where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth.

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Description of the reverse stock split arrangement. Also provide the retroactive effect given by the reverse split that occurs after the balance sheet date but before the release of financial statements.

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-Publisher FASB

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- Definition

Per share amount of par value or stated value of stock classified as temporary equity. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable.

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Business acquisition number of shares acquired.

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Collaborative arrangement consideration received shares.

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Collaborative arrangement consideration received value.

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Collaborative arrangement royalty rate as percentage of gross profit.

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Increase (decrease) in equity securities.

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Shares of common stock purchased from collaborative partners.

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Shares purchased price per share.

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Rate per annum to which holders of the redeemable convertible preferred stock shall be entitled to receive dividends, when and if declared.

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