Note 9 - Non-recourse Long-term Debt, Net (Details Textual) - Royalty-backed Loan [Member] - USD ($) $ in Millions		6 Months Ended
Nov. 04, 2016	Sep. 30, 2018
Proceeds from Issuance of Long-term Debt, Total	$ 50
Debt Instrument, Interest Rate, Stated Percentage	9.50%
Percentage of Royalty Payments in Excess of Accrued Loan Interest to be Applied to Principal		50.00%

The percentage of royalties received in excess of interest on an associated loan that will be applied to paying down principal on the loan under a royalty agreement.

No definition available.

+ Details

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Namespace Prefix:	pgnx_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	na
Period Type:	instant

- Definition

The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3255-108585

+ Details

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Balance Type:	debit
Period Type:	duration

- Details

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Namespace Prefix:
Data Type:	na
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Period Type: