Collaboration and Other Agreements - Pre-tax Profit (Loss) Under the Agreement (Details) (USD $)	1 Months Ended	3 Months Ended
Dec. 31, 2011	Mar. 31, 2015	Mar. 31, 2014
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
50% of Pharmacyclics' U.S. product revenue, net		$ 189,158,000us-gaap_SalesRevenueGoodsNet	$ 56,179,000us-gaap_SalesRevenueGoodsNet
Less: 50% of Pharmacyclics' U.S. cost of goods sold		(16,702,000)us-gaap_CostOfGoodsSold	(6,110,000)us-gaap_CostOfGoodsSold
Less: Pharmacyclics' share of research and development costs under the Agreement, net of Excess Amounts		(49,377,000)us-gaap_ResearchAndDevelopmentExpense	(35,292,000)us-gaap_ResearchAndDevelopmentExpense
Collaboration and License Agreement with Janssen Biotech Inc [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Less: Pharmacyclics' share of research and development costs under the Agreement, net of Excess Amounts		(27,332,000)	(24,402,000)
Maximum Cost Sharing Amount Incurred	50,000,000	50,000,000
Pharmacyclic [Member] \| IMBRUVICA [Member] \| Collaboration and License Agreement with Janssen Biotech Inc [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
50% of Pharmacyclics' U.S. product revenue, net		94,579,000	28,090,000
Less: 50% of Pharmacyclics' U.S. cost of goods sold		(8,351,000)	(3,055,000)
Pharmacyclics' 50% share of U.S. net product revenue less cost of goods sold		86,228,000	25,035,000
Less: Pharmacyclics' share of U.S. commercial expenses under the Agreement		(15,083,000)	(14,593,000)
Pharmacyclics' share of U.S. pre-tax profits from the commercialization of IMBRUVICA under the Agreement		71,145,000	10,442,000
Add: Pharmacyclics' share of ex-U.S. pre-tax commercial profit (loss) under the Agreement (1)		12,525,000	(3,572,000)
Pharmacyclics' share of worldwide pre-tax profits from the commercialization of IMBRUVICA under the Agreement		83,670,000	6,870,000
Less: Pharmacyclics' share of research and development costs under the Agreement, net of Excess Amounts		(27,332,000)	(24,402,000)
Total pre-tax profit (loss) under the Agreement		$ 56,338,000	$ (17,532,000)

Collaboration Agreement, Share of Non-U.S. Pre-tax Commercial Profits (Losses)

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Collaboration Agreement, Share of U.S. Pre-tax Profits (Losses) from Commercialization

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- Definition

Collaborative Arrangement, Share of Product Revenue, Net of Cost of Good Sold

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Collaborative Arrangement, Share of U.S. Commercial Expenses

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Net Profit (Loss) Under Collaborative Agreement

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- Definition

Worldwide Pre Tax Commercial Profit (Loss) Under Collaborative Agreement, Amount

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No definition available.

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- Definition

Total costs related to goods produced and sold during the reporting period.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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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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- Definition

Aggregate revenue during the period from the sale of goods in the normal course of business, after deducting returns, allowances and discounts.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

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