8. Accounts Payable and Accrued Expenses (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Accounts payable and accrued expenses
Accounts payable	$ 17us-gaap_AccountsPayableCurrent	$ 6us-gaap_AccountsPayableCurrent
Accrued audit & professional	37us-gaap_AccruedProfessionalFeesCurrent	38us-gaap_AccruedProfessionalFeesCurrent
Accrued consulting fees-related party	1PGAI_AccruedConsultingFeesRelatedParty	1PGAI_AccruedConsultingFeesRelatedParty
Environmental remediation obligations	61	64
Accrued debenture fees	122PGAI_AccruedDebentureFees	119PGAI_AccruedDebentureFees
Accrued miscellaneous	2PGAI_AccruedMiscellaneous	1PGAI_AccruedMiscellaneous
Total	240	229
Accrued real estate taxes consisted of:
Current real estate taxes	$ 2	$ 8

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- Definition

Custom Element.

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- Definition

Custom Element.

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Sum of the carrying values as of the balance sheet date of obligations incurred through that date and due within one year (or the operating cycle, if longer), including liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received, taxes, interest, rent and utilities, accrued salaries and bonuses, payroll taxes and fringe benefits.

+ References

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Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Total costs accrued as of the balance sheet date for environmental loss contingencies.

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Carrying value as of the balance sheet date of obligations incurred and payable for real and property taxes.

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Carrying value as of the balance sheet date of obligations incurred through that date and payable for professional fees, such as for legal and accounting services received. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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