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Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(i)) -URI http://asc.fasb.org/extlink&oid=6881521&loc=d3e23780-122690 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 08 -Paragraph i -Article 4 false1Balance at end of period (in shares)24false 4us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExercisePriceus-gaap_truenainstantfalsefalsefalsefalsefalsefalsefalsefalselabel1truefalsefalse0.320.32USD$falsetruefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalsenum:perShareItemTypedecimalAgreed-upon price for the exchange of the underlying asset relating to the share-based payment award.No definition available.false3Weighted average exercise price (in dollars per share)25false 4us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsOutstandingWeightedAverageRemainingContractualTermsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalselabel1falsefalsefalse001 year 8 months 16 daysfalsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalsexbrli:durationItemTypenaWeighted average remaining contractual term for equity-based awards excluding options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (e)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 false0Remaining term of warrants26false 4erhe_WarrantsPriceIntrinsicValueerhe_falsenainstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse00USD$falsetruefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryThe intrinsic value of stock warrants as of the balance sheet date.No definition available.false2Warrants price intrinsic valuefalseSTOCKHOLDERS' EQUITY (Details) (USD $)NoRoundingNoRoundingNoRoundingUnKnowntruefalsefalseSheethttp://erhc.com/role/StockholdersEquityDetails326