Fair Value Measurements (Financial Instruments Measured at Fair Value on a Recurring Basis) (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Financial assets:
Foreign Currency Contract, Asset, Fair Value Disclosure	$ 4,069	$ 0
Royalty rights	259,244pdli_Royaltyrights	235,677pdli_Royaltyrights
Cash, Cash Equivalents and Available-for-Sale Securities, Fair Value	293,687	99,540
Assets, Fair Value	487,415us-gaap_AssetsFairValueDisclosure	326,885us-gaap_AssetsFairValueDisclosure
Financial liabilites:
Foreign currency hedge contracts	0	8,871
Money Market Funds [Member]
Financial assets:
Cash and Cash Equivalents, Fair Value	221,792	85,970
Equity Securities [Member]
Financial assets:
Available for Sale Securities, Fair Value	2,310	5,238
Fair Value Level 1 [Member]
Financial assets:
Assets, Fair Value	221,792	85,970
Financial liabilites:
Foreign currency hedge contracts	0	0
Fair Value Level 1 [Member] \| Money Market Funds [Member]
Financial assets:
Cash and Cash Equivalents, Fair Value	221,792	85,970
Fair Value Level 1 [Member] \| Equity Securities [Member]
Financial assets:
Available for Sale Securities, Fair Value	0	0
Fair Value Level 2 [Member]
Financial assets:
Foreign Currency Contract, Asset, Fair Value Disclosure	4,069
Assets, Fair Value	6,379	5,238
Financial liabilites:
Foreign currency hedge contracts	0	8,871
Fair Value Level 2 [Member] \| Money Market Funds [Member]
Financial assets:
Cash and Cash Equivalents, Fair Value	0	0
Fair Value Level 2 [Member] \| Equity Securities [Member]
Financial assets:
Available for Sale Securities, Fair Value		5,238
Fair Value Level 3 [Member]
Financial assets:
Royalty rights	259,244	235,677
Assets, Fair Value	$ 259,244	$ 235,677

Cash, cash equivalents and available-for-sale securities valued at fair value.

No definition available.

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- Definition

Royalty rights

+ References

No definition available.

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- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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- Definition

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 25

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=28360136&loc=d3e22054-111558

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 5

-Subparagraph (aa)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26610-111562

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- Definition

Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Cash

-URI http://asc.fasb.org/extlink&oid=6506951

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Cash Equivalents

-URI http://asc.fasb.org/extlink&oid=6507016

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- Definition

Fair value portion of asset contracts related to the exchange of different currencies, including, but not limited to, foreign currency options, forward contracts, and swaps.

+ References

No definition available.

+ Details

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- Definition

Fair value portion of liability contracts related to the exchange of different currencies, including, but not limited to, foreign currency options, forward (delivery or nondelivery) contracts, and swaps entered into.

+ References

No definition available.

+ Details

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