Net Income per Share (Net Income Per Basic and Diluted Share) (Parentheticals) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2013	Mar. 31, 2012
Net income per share
Estimated tax on interest expense on convertible notes	$ 3	$ 15

The estimated tax on interest expense recognized in the period associated with any convertible debt.

No definition available.

Name:	pdli_EstimatedTaxOnConvertibleNoteInterestExpense
Namespace Prefix:	pdli_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration