License And Development Contract Liability

No definition available.

Name:	erii_LicenseAndDevelopmentContractLiability
Namespace Prefix:	erii_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

License Term

+ References

No definition available.

+ Details

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- Definition

Amount due to be received upon reaching the milestone from.

+ References

No definition available.

+ Details

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- Definition

The number of milestone payments to be received as per the agreement.

+ References

No definition available.

+ Details

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- Definition

Amount received for the up front non-refundable payment that will be recognized over the length of the agreement.

+ References

No definition available.

+ Details

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- Definition

Revenue earned during the period relating to consideration received from another party for the right to use, but not own, certain of the entity's intangible assets. Licensing arrangements include, but are not limited to, rights to use a patent, copyright, technology, manufacturing process, software or trademark. Licensing fees are generally, but not always, fixed as to amount and not dependent upon the revenue generated by the licensing party. An entity may receive licensing fees for licenses that also generate royalty payments to the entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1(e))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- 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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- Details

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- Details

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- Details

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- Details

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Recent Accounting Pronouncements - Additional Details (Details) $ in Thousands		3 Months Ended		6 Months Ended		12 Months Ended
	Oct. 14, 2015 USD ($) payment	Jun. 30, 2018 USD ($)	Jun. 30, 2017 USD ($)	Jun. 30, 2018 USD ($)	Jun. 30, 2017 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
License and development revenue		$ 3,358	$ 3,050	$ 6,107	$ 5,298	$ 11,106	$ 8,069	$ 1,332
License and development contract liability						54,493	65,599
As Previously Reported
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
License and development revenue			1,250		2,500	5,000	5,000	1,042
License and development contract liability						63,958	68,958
Accounting Standards Update 2014-09 \| Restatement Adjustment
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
License and development revenue			$ 1,800		$ 2,798	6,106	3,069	$ 290
License and development contract liability						$ 9,465	$ 3,359
VorTeq License Agreement
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Up front non-refundable payment	$ 75,000
License term	15 years
Number of milestone payments \| payment	2
Milestone Payment One Upon Successful Yard Test \| VorTeq License Agreement
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
VorTeq milestone payment to be received	$ 25,000