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16. REVENUES (Details Narrative) - USD ($) | Dec. 31, 2018 | Dec. 31, 2017
--- | --- | ---
Deferred revenue | $ 835,785 | $ 77,514
Product Deposits [Member] |  |
Deferred revenue | 791,913 |
Maintenance Fees [Member] |  |
Deferred revenue | $ 43,872 |

X
- Definition Amount of deferred revenue as of balance sheet date. Deferred revenue represents collections of cash or other assets related to a revenue producing activity for which revenue has not yet been recognized. Generally, an entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP. + References No definition available. + Details
Name: | us-gaap_DeferredRevenue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Details
Name: | us-gaap_DeferredRevenueArrangementTypeAxis=evsi_ProductDepositsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DeferredRevenueArrangementTypeAxis=evsi_MaintenanceFeesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |