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Disposal Group, Including Discontinued Operation, Ownership To Be Disposed

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Represents the information pertaining to payable of exit fees in the operation for second or fourth year.

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Amount of contractual obligation, including but not limited to, long-term debt, capital lease obligations, operating lease obligations, purchase obligations, and other commitments.

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Fair value of the assets less the liabilities of a derivative or group of derivatives.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
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Amount of consideration received or receivable for the disposal of assets and liabilities, including discontinued operation.

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The amount of expense provided in the period for legal costs incurred on or before the balance sheet date pertaining to resolved, pending or threatened litigation, including arbitration and mediation proceedings.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Amount awarded to other party in judgment or settlement of litigation.

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The value (monetary amount) of the award the plaintiff seeks in the legal matter.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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The total number of new claims filed pertaining to a loss contingency during the period.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Number of pending claims pertaining to a loss contingency.

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The amount of cash paid for the settlement of litigation or for other legal issues during the period.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Section 45
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Cash received for the settlement of litigation during the current period.

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Minimum amount of purchase arrangement in which the entity has agreed to expend funds to procure goods or services from a supplier.

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Commitments and contingencies (Details) ¥ in Thousands						1 Months Ended												12 Months Ended
Commitments and contingencies (Details) ¥ in Thousands	Jan. 31, 2019 USD ($)	Oct. 25, 2017 USD ($)	Oct. 25, 2017 CNY (¥)	Jun. 16, 2017 USD ($)	Dec. 27, 2016 USD ($)	Dec. 31, 2019 USD ($)	Aug. 31, 2019 USD ($)	Feb. 28, 2019 USD ($)	Feb. 28, 2019 CNY (¥)	Jan. 31, 2019 USD ($)	Dec. 31, 2018 USD ($) lawsuit	Dec. 31, 2018 CNY (¥) lawsuit	Nov. 30, 2018 USD ($)	Nov. 30, 2018 CNY (¥)	Jul. 31, 2018 USD ($)	Apr. 30, 2018 USD ($)	Nov. 30, 2016 lawsuit	Dec. 31, 2019 USD ($)	Dec. 31, 2010 lawsuit claim	Dec. 31, 2017 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2012 USD ($)
Commitments And Contingencies Disclosure [Line Items]
Number of defendants \| lawsuit																			4
Total outstanding purchase obligations						$ 62,100,000												$ 62,100,000
Fair value of derivative											$ 2,000,000.0									$ 400,000
Russian federation
Commitments And Contingencies Disclosure [Line Items]
Exit fees for future																		2,000,000.0
Embedded Derivative Financial Instruments \| Maximum
Commitments And Contingencies Disclosure [Line Items]
Other non-current liability																					$ 5,000,000.0
Indemnification Agreement
Commitments And Contingencies Disclosure [Line Items]
Payment for legal settlement																		$ 0
Performance guarantee \| Private Placement
Commitments And Contingencies Disclosure [Line Items]
Other non-current liability											$ 6,700,000											$ 30,000,000.0
Rusnano Group \| NeoPhotonics Corporation, LLC \| Disposal Group, Not Discontinued Operations
Commitments And Contingencies Disclosure [Line Items]
Ownership to be disposed											100.00%
Consideration received pursuant to asset purchase agreement											$ 3,000,000.0
Penalty payment cancellation											$ 1,000,000.0
Oyster Communications, Inc.
Commitments And Contingencies Disclosure [Line Items]
New claims filed, number \| lawsuit																	9
Finisar Corp
Commitments And Contingencies Disclosure [Line Items]
Pending claims \| claim																			2
Lestina International Ltd. litigation
Commitments And Contingencies Disclosure [Line Items]
Damages sought, value					$ 3,000,000.0
Lawsuit Filed by Lestina International Ltd. \| NeoPhotonics Dongguan Co., Ltd \| Lestina International Ltd.
Commitments And Contingencies Disclosure [Line Items]
Loss contingency, damages awarded, value										$ 2,200,000
APAT OE Legal Dispute
Commitments And Contingencies Disclosure [Line Items]
Damages sought, value																$ 20,000,000.0
APAT OE Legal Dispute \| APAT OE
Commitments And Contingencies Disclosure [Line Items]
New claims filed, number \| lawsuit											2	2
APAT OE and NeoChina
Commitments And Contingencies Disclosure [Line Items]
Damages sought, value											$ 7,600,000	¥ 50,900
Assets ordered to be preserved	$ 3,800,000									$ 3,800,000	$ 29,000,000.0
Claim Against APAT OE and Zheijiang Merchants Property Insurance Company \| NeoChina
Commitments And Contingencies Disclosure [Line Items]
Damages sought, value								$ 52,000	¥ 350
APAT Arbitration
Commitments And Contingencies Disclosure [Line Items]
Damages sought, value				$ 1,500,000			$ 8,100,000	$ 7,100,000					$ 7,800,000		$ 12,000,000.0
Damages awarded to company		$ 110,000	¥ 700
Attorney fees													$ 121,000	¥ 810
Cisco Settlement Agreement
Commitments And Contingencies Disclosure [Line Items]
Loss contingency, damages awarded, value	$ 300,000
Amount awarded to other party, production credits						$ 200,000