Other Current Assets (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Mar. 31, 2013
Other Current Assets
Prepaid insurance & rent	$ 281	$ 276
Land purchase option		500
Other	40	395
Total other current assets	$ 321	$ 1,171

Carrying amount as of the balance sheet date of SK Land Holdings option.

No definition available.

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

Carrying amount as of the balance sheet date of unamortized costs of insurance coverage and rental payments made in advance of the rental period, both of which will be charged against earnings ratably over the period which they cover; such amounts will be charged against earnings within one year or the normal operating cycle, if longer.

+ References

No definition available.

+ Details

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Namespace Prefix:	pgrx_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Aggregate carrying amount, as of the balance sheet date, of current assets not separately disclosed in the balance sheet. Current assets are expected to be realized or consumed within one year (or the normal operating cycle, if longer).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.8)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 8

-Article 5

+ Details

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- Definition

Carrying amount, as of the balance sheet date, of current assets which have not been itemized or categorized in the footnotes to the financial statements and are a component of Other Assets, Current (OtherAssetsCurrent). Current assets are expected to be realized or consumed within one year (or the normal operating cycle, if longer).

+ References

No definition available.

+ Details

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