Note 13 - Employee Benefit Plans (Details Textual) - USD ($)	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Defined Contribution Plan, Contributions By Plan Participants Percentage	15.00%
Defined Contribution Plan, Employer Matching Contribution, Percent of Match	10.00%	10.00%
Defined Contribution Plan, Employer Discretionary Contribution Amount	$ 36,800	$ 35,400
Employee Stock Ownership Plan (ESOP), Cash Contributions to ESOP	$ 0	$ 0

As a percent of gross pay, the maximum percentage of contributions by plan participants to the employee savings plan which are eligible for employer matching contributions.

No definition available.

+ Details

Name:	relv_DefinedContributionPlanContributionsByPlanParticipantsPercentage
Namespace Prefix:	relv_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of discretionary contributions made by an employer to a defined contribution plan.

+ References

No definition available.

+ Details

Name:	us-gaap_DefinedContributionPlanEmployerDiscretionaryContributionAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Percentage employer matches of the employee's percentage contribution matched.

+ References

No definition available.

+ Details

Name:	us-gaap_DefinedContributionPlanEmployerMatchingContributionPercentOfMatch
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

This item represents the amount of cash contributions during the period made by the entity to the Employee Stock Ownership Plan (ESOP).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 40
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109244661&loc=d3e17540-113929

+ Details

Name:	us-gaap_EmployeeStockOwnershipPlanESOPCashContributionsToESOP
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration