XML 67 R46.htm IDEA: XBRL DOCUMENT
v3.7.0.1

Collaboration Agreements (Bristol-Myers Squibb Collaboration) (Details) - Collaborative Arrangement, 2 BMS Compound Utilized [Member] [Member] | 6 Months Ended
--- | ---
Jun. 30, 2017
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items] |
Share in costs, percentage | 33.33%
BMS [Member] |
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items] |
Share in costs, percentage | 66.67%

X
- Definition Collaborative Arrangement, Share in Costs, Percentage + References No definition available. + Details
Name: | exel_CollaborativeArrangementShareinCostsPercentage
Namespace Prefix: | exel_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition 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. + References No definition available. + Details
Name: | us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_TypeOfArrangementAxis=exel_CollaborativeArrangementwithTwoBristolMyersSquibbCompoundUtilizedMemberMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dei_LegalEntityAxis=exel_BristolMyersSquibbMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |