Date the debt instrument was issued, in YYYY-MM-DD format.

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

- Definition

Date when the debt instrument is scheduled to be fully repaid, in YYYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)(i)
-Publisher FASB
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 210
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-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22)(a)(2))
-Publisher FASB
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Reference 4: http://www.xbrl.org/2003/role/exampleRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1B

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Amount of borrowings from a bank classified as other, maturing within one year or operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(19)(a)(1))
-Publisher FASB
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16)(a)(1))
-Publisher FASB
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479170/946-210-S99-1

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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

No definition available.

+ Details

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

- Definition

The portion of the carrying amount of short-term borrowings outstanding as of the balance sheet date which accrues interest at a set, unchanging rate.

+ References

No definition available.

+ Details

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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Details

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Period Type:

- Details

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Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=ncl_AgriculturalBankOfChinaChangzhouZhonglouSubbranchMember
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Bank Borrowings - Schedule of Weighted Average Interest Rate for the Short-Term Loan (Detail) - USD ($)	3 Months Ended
	Mar. 31, 2025	Dec. 31, 2024	Mar. 31, 2024
Short-Term Debt [Line Items]
Interest rate	5.72%		4.71%
Short-Term Debt	$ 4,778,357	$ 4,699,081
Industrial and Commercial Bank of China [Member]
Short-Term Debt [Line Items]
Loan period - Date of Issuance	Jun. 04, 2024
Loan period - Date of maturity	Jun. 12, 2025
Interest rate	4.35%
Short-Term Debt	$ 1,393,107	1,369,994
Industrial and Commercial Bank of China [Member]
Short-Term Debt [Line Items]
Loan period - Date of Issuance	Jun. 04, 2024
Loan period - Date of maturity	Jun. 10, 2025
Interest rate	4.35%
Short-Term Debt	$ 1,393,107	1,369,994
Jiangnan Rural Commercial Bank [Member]
Short-Term Debt [Line Items]
Loan period - Date of Issuance	Feb. 28, 2024
Loan period - Date of maturity	Feb. 27, 2025
Interest rate	4.79%
Short-Term Debt	$ 1,253,796	1,232,994
Agricultural Bank of China, Changzhou Zhonglou Sub-branch [Member]
Short-Term Debt [Line Items]
Loan period - Date of Issuance	Jul. 26, 2024
Loan period - Date of maturity	Jul. 25, 2025
Interest rate	3.25%
Short-Term Debt	$ 738,347	$ 726,097