| **Interim Financial Statements (Details) (USD $)**                                          | 3 Months Ended | 9 Months Ended | 12 Months Ended |              |
|---------------------------------------------------------------------------------------------|----------------|----------------|-----------------|--------------|
||
| **PRO 140 [Abstract]**                                                                      |           |           |            |         |   |   |
| Proceeds From License Fees Received PRO 140                                                 | $ 3,500,000    |           |            |         |   |   |
| **Eligible to receive [Abstract]**                                                          |           |           |            |         |   |   |
| Percentage Of Royalties                                                                     |           | 5.00%          | 5.00%           |         |   |   |
| Maximum License Fee Receivable On Commencement Of US Or Ex US Phase 3 Trial Of PRO 140      |           | 1,500,000      | 1,500,000       |         |   |   |
| Maximum License Fee Receivable Upon US Or EU Marketing Approval Of PRO 140                  |           | 5,000,000      | 5,000,000       |         |   |   |
| **Relistor [Abstract]**                                                                     |           |           |            |         |   |   |
| Number of countries approved sale of Relistor                                               |           | 50             | 50              |         |   |   |
| Receipt of upfront ex-U.S. sublicensee revenue                                              |           |           |            |         | 200,000 |   |
| **Eligible to receive**                                                                     |           |           |            |         |   |   |
| License fee receivable on U.S. Marketing approval for subcutaneous Relistor, maximum        |           | 40,000,000     | 40,000,000      |         |   |   |
| License fee receivable on U.S. Marketing approval for oral formulation of Relistor, maximum |           | 50,000,000     | 50,000,000      |         |   |   |
| Payment receivable on achievement of specified U.S. sales targets                           |           | 200,000,000    | 200,000,000     |         |   |   |
| Percentage of royalties, minimum (in hundredths)                                            |           | 15.00%         | 15.00%          |         |   |   |
| Percentage of royalties, maximum (in hundredths)                                            |           | 19.00%         | 19.00%          |         |   |   |
| Percentage of upfront, milestone, reimbursement or other revenue (in hundredths)            |           | 60.00%         | 60.00%          |         |   |   |
| Annual U.S. sales, minimum                                                                  |           |           | 100,000,000     |         |   |   |
| **Funding and Financial Matters [Abstract]**                                                |           |           |            |         |   |   |
| Cash and cash equivalents at end of period                                                  |           | 41,096,000     | 41,096,000      | 77,998,000   | 70,105,000 | 47,918,000 |
| Decrease in cash and cash equivalents                                                       |           | 6,700,000      | 29,009,000      | (30,080,000) |   |   |
| Minimum number of years cash will fund operations (in years)                                |           |           | 1 year          |         |   |   |
| Authorized amount of common shares under stock repurchase program, maximum                  |           |           | 15,000,000      |         |   |   |
| Remaining authorized amount of common shares under stock repurchase program                 |           |           | 12,300,000      |         |   |   |
| Stock repurchased during the period, value                                                  |           | $ 0            | $ 0             |         |   |   |

| X                                                                                                                                                                                                                                                                                                                                          |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Represents minimum amount of annual sales required to be considered as a commercialization milestone for payment of license fee.
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No definition available.
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| X                                                                                                                                                             |
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| X                                                                                                                                                                    |
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| X                                                                                                                                                                                                                                                                                                                                                                                                                      |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Represents the maximum amount of license fee receivable by the entity subsequent to commencement of a U.S. or ex-U.S. equivalent phase 3 trial of PRO 140.
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                          |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Represents the maximum amount of license fee receivable by the entity subsequent to approval accorded by U.S marketing for oral formulation of Relistor.
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                          |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Represents the maximum amount of license fee receivable by the entity subsequent to approval accorded by U.S marketing for subcutaneous Relistor in non-cancer pain patients.
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                    |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Represents the maximum amount of license fee receivable by the entity subsequent to U.S. or EU marketing approval of of PRO 140.
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                             |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Represents the maximum amount of milestone payment receivable by the entity subsequent to achievement of U.S. sales target as specified by U.S. Marketing.
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No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                         |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Represents total number of countries other than the domestic nation which have approved one of the entity's products to be sold in their localities.
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No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                      |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
We expect that the cash and cash equivalents will be sufficient to fund operations as currently anticipated beyond one year.
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No definition available.
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| X                                                                                                                                                                                                                                                                    |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Represents percentage of royalties upon net sales by licensees.
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No definition available.
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| X                                                                                                                                                                                                                                                                                   |
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| - Definition
Represents maximum percentage of royalties upon net sales by licensees.
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| X                                                                                                                                                                                                                                                                                   |
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Represents minimum percentage of royalties upon net sales by licensees.
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| X                                                                                                                                                                                                                                                                                                                                                                                         |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Represents percentage of upfront fee, reimbursement, other revenue, milestone payments received by entity's licensees outside the domestic nation.
+ References
No definition available.
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| X                                                                                                                                            |
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| X                                                                                                                                                                                                                                                                                                    |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Cash received from licensees for license fees during the current period.
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No definition available.
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| X                                                                                                                                                                                                                                                                                                                        |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Represents amount of cash received as an upfront fee in respect of ex-U.S. sublicensee revenue.
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No definition available.
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| X                                                                                                                                              |
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|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount 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. Excludes cash and cash equivalents within disposal group and discontinued operation.
+ References
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|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of increase (decrease) in cash and cash equivalents. Cash and cash equivalents are the amount 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. Excludes cash and cash equivalents within disposal group and discontinued operation.
+ References
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|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Equity impact of the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.
+ References
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| X                                                                                                                                                                                                                                                                                                                          |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The amount authorized by an entity's Board of Directors under a stock repurchase plan.
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No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                  |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The remaining repurchase amount authorized by an entity's Board of Directors under a stock repurchase plan.
+ References
No definition available.
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