| **Proposed Acquisition by Duke Energy Corporation (Details) - USD ($) $ / shares in Units, $ in Millions** | 3 Months Ended | 9 Months Ended |        |        |
|------------------------------------------------------------------------------------------------------------|----------------|----------------|--------|--------|
||
| **Business Combinations [Abstract]**                                                                       |           |           |   |   |
| Business Acquisition, Date of Acquisition Agreement                                                        |           | Oct. 24,  2015 |   |   |
| Business Acquisition, Share Price                                                                          |           |           |   | $ 60   |
| Shareholder Approval Vote, Percentage Amount                                                               |           |           | 66.80% |   |
| Business Combination, Acquisition Related Costs                                                            | $ 0.6          | $ 2.6          |   |   |
| Business Acquisition, Incremental Share Based Compensation, Acceleration                                   | $ 0.6          | $ 6.0          |   |   |

| X                                                                                                                                                                                                                                                                                                                                                                    |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The incremental share-based compensation expense related to acceleration of incentive compensation plan awards.
+ References
No definition available.
+ Details**Name:**pny_BusinessAcquisitionIncrementalShareBasedCompensationAcceleration**Namespace Prefix:**pny_**Data Type:**xbrli:monetaryItemType**Balance Type:**debit**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                                                              |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Approval percentage of proposed acquisition by shareholders of outstanding common stock entitled to vote.
+ References
No definition available.
+ Details**Name:**pny_ShareholderApprovalVotePercentageAmount**Namespace Prefix:**pny_**Data Type:**num:percentItemType**Balance Type:**na**Period Type:**instant |
| X                                                                                                                                                                                                                                                                                                                    |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Date when the business acquisition agreement was executed, in CCYY-MM-DD format.
+ References
No definition available.
+ Details**Name:**us-gaap_BusinessAcquisitionDateOfAcquisitionAgreement1**Namespace Prefix:**us-gaap_**Data Type:**xbrli:dateItemType**Balance Type:**na**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                                                                |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Price of a single share of a number of saleable stocks paid or offered to be paid in a business combination.
+ References
No definition available.
+ Details**Name:**us-gaap_BusinessAcquisitionSharePrice**Namespace Prefix:**us-gaap_**Data Type:**num:perShareItemType**Balance Type:**na**Period Type:**instant |
| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 25 -Paragraph 23 -URI http://asc.fasb.org/extlink&oid=73531572&loc=d3e1043-128460
+ Details**Name:**us-gaap_BusinessCombinationAcquisitionRelatedCosts**Namespace Prefix:**us-gaap_**Data Type:**xbrli:monetaryItemType**Balance Type:**debit**Period Type:**duration |
| X                                                                                                                                                                                                      |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - References
No definition available.
+ Details**Name:**us-gaap_BusinessCombinationsAbstract**Namespace Prefix:**us-gaap_**Data Type:**xbrli:stringItemType**Balance Type:**na**Period Type:**duration |