Notes Receivable (Details) ¥ in Millions	Jun. 30, 2025 USD ($)	Jun. 30, 2025 CNY (¥)	Jun. 30, 2024 USD ($)
Notes Receivable [Line Iems]
Notes receivable			$ 1,885,183
Notes receivable	81,047,591	¥ 581
Notes receivable yet to mature	$ 4,521,445	¥ 32

Represents the amount of notes receivable yet to pay.

No definition available.

Name:	npt_NotesReceivableYetToPay
Namespace Prefix:	npt_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amortized cost, after allowance for credit loss, of financing receivable classified as current. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
-SubTopic 10
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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount due from parties in nontrade transactions, classified as other.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant