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Carrying Value of Equity Interest Owned Prior to Acquisition

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Ownership of the issued and outstanding stock of Cell Design Labs, Inc. acquired through Kite acquisition

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Regulatory Milestone-based Payments, Maximum

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The amount of stock-based awards replacement attributable to the post combination period excluded from the consideration transferred

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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.

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Price of a single share of a number of saleable stocks paid or offered to be paid 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 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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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of increase (decrease) in carrying value of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition.

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Amount before 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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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the 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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The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

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Acquisitions Business Combination Details- Narrative (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended	3 Months Ended	12 Months Ended
	Oct. 31, 2017	Dec. 31, 2017	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Oct. 03, 2017
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Indefinite-Lived Intangible Assets						$ 8,950
Business Combination, Consideration Transferred	$ 11,155
Business Combination, Consideration Transferred, Equity Interests Issued and Issuable	75
Goodwill Acquired From Business Combination						2,945
Goodwill, Period Increase (Decrease)				$ (42)
Research and development expenses			$ 9,106	$ 5,018	$ 3,734
Payments to Outstanding Common Stockholders [Member]
Business Acquisition [Line Items]
Payments to Acquire Businesses, Gross	10,420
Payments to Vested Equity Award Holders [Member]
Business Acquisition [Line Items]
Payments to Acquire Businesses, Gross	645
Payments to Warrant Holders [Member]
Business Acquisition [Line Items]
Payments to Acquire Businesses, Gross	$ 15
Share Based Compensation Expense [Member]
Business Acquisition [Line Items]
Business Acquisition, Equity Interest Issued or Issuable, Value Assigned						$ 733
Kite Pharma, Inc [Member]
Business Acquisition [Line Items]
Business Acquisition, Share Price						$ 180
Intangible Asset - axicabtagene ciloleucel (DLBCL) [Member]
Business Acquisition [Line Items]
Finite-Lived Intangible Assets, Period Increase (Decrease)		$ 6,200
Finite-Lived Intangible Asset, Useful Life		18 years
Intangible Asset - Daiichi Sankyo [Member]
Business Acquisition [Line Items]
Finite-lived Intangible Assets Acquired		$ 91
Finite-Lived Intangible Asset, Useful Life		14 years
Cell Design Labs, Inc. [Member]
Business Acquisition [Line Items]
Ownership Cell Design Labs, Inc.						12.20%
Asset Acquisition Cash Outflow		$ 150
Regulatory Milestone-based Payments, Maximum		322			$ 322
Carrying Value of Equity Interest Owned Prior to Acquisition						$ 30
Research and development expenses		$ 172