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The average effective interest rate during the reporting period.

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-Topic 210
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-Topic 470
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Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 835
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Increase for accrued, but unpaid interest on the credit facility for the period.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 235
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Disclosure of timing of required repayments, sinking fund requirements, and other redeemable securities at fixed or determinable prices and dates in the five years immediately following the date of the latest balance sheet presented in the financial statements, and the amount thereafter to fully repay the principal of long-term debt. These disclosures may be made either on an individual debt or security basis, by type of debt or security basis, or on a combined basis.

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The cash inflow from a borrowing having initial term of repayment within one year or the normal operating cycle, if longer.

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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.

No definition available.

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Name:	us-gaap_DebtInstrumentAxis=GRST_MirageRealtyMember
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Name:	us-gaap_DebtInstrumentAxis=GRST_ThirdPartyMember
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Name:	us-gaap_DebtInstrumentAxis=GRST_RevolvingLineOfCreditMember
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