Commitments and Contingencies (Details Textuals) (USD $) In Thousands	Jun. 30, 2011	Dec. 31, 2010
Commitments and Contingencies (Textuals) [Abstract]
Liabilities related to indemnification obligations	$ 0	$ 0

Name:

nktr_LiabilitiesRelatedToIndemnificationObligation

Namespace Prefix:

nktr

Data Type:

xbrli:monetaryItemType

Balance Type:

credit

Period Type:

instant