The amount of a specific compensating balance arrangement that is maintained under an agreement for a bank loan or future credit availability.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.1)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

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Namespace Prefix:	us-gaap_
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

No definition available.

+ Details

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

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentTerm
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Fair value of the amount outstanding under the credit facility.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=123594938&loc=d3e13433-108611

+ Details

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

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

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

- Details

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Namespace Prefix:
Data Type:	na
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- Details

Name:	srt_StatementGeographicalAxis=country_CN
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- Details

Name:	srt_RangeAxis=srt_MinimumMember
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- Details

Name:	srt_RangeAxis=srt_MaximumMember
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- Details

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- Details

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Data Type:	na
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- Details

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- Details

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- Details

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Namespace Prefix:
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Debt - Notes Payable and Short-term Borrowing (Details)	6 Months Ended
Debt - Notes Payable and Short-term Borrowing (Details)	Jun. 30, 2021 USD ($)	Jun. 17, 2021 CNY (¥)	Jun. 17, 2021 USD ($)	Dec. 31, 2020 USD ($)
Notes payable \| China \| Minimum
Debt Instrument [Line Items]
Debt instrument, term	3 months
Notes payable \| China \| Maximum
Debt Instrument [Line Items]
Debt instrument, term	6 months
Bankers acceptance
Debt Instrument [Line Items]
Restricted cash and investments, current	$ 0			$ 0
Bankers acceptance \| Subsidiaries
Debt Instrument [Line Items]
Outstanding balance of line of credit facilities	$ 0			$ 0
Credit Line Agreement \| Notes payable \| China \| Subsidiaries \| NeoPhotonics China
Debt Instrument [Line Items]
Credit facility, maximum borrowing amount		¥ 120,000,000	$ 18,600,000
Credit Line Agreement \| Notes payable \| China \| Subsidiaries \| NeoPhotonics Donggua
Debt Instrument [Line Items]
Credit facility, maximum borrowing amount		¥ 30,000,000	$ 4,600,000