Name:	amch_DebtInstrumentMinimumLiquidityRequirements
Namespace Prefix:	amch_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Represents the threshold minimum percentage of voting stock.

No definition available.

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Namespace Prefix:	amch_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

Represents the threshold percentage of annual excess cash flow.

No definition available.

Name:	amch_ThresholdPercentageOfAnnualExcessCashFlow
Namespace Prefix:	amch_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

Represents the Threshold percentage of annual excess cash flow if net leverage ratio is attained.

No definition available.

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Namespace Prefix:	amch_
Data Type:	dtr-types:percentItemType
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Represents the threshold percentage of equity interests pledged.

No definition available.

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Data Type:	dtr-types:percentItemType
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Represents the threshold percentage of net cash proceeds of non-ordinary course asset sales.

No definition available.

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Namespace Prefix:	amch_
Data Type:	dtr-types:percentItemType
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Represents the threshold percentage of net proceeds of issuance or incurrence of debt.

No definition available.

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Namespace Prefix:	amch_
Data Type:	dtr-types:percentItemType
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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

No definition available.

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

Contractual interest rate for funds borrowed, under the debt agreement.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1B
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-Name Accounting Standards Codification
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-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

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.

Name:	us-gaap_DebtInstrumentLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Number of new stock issued during the period.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Name:	us-gaap_StockIssuedDuringPeriodSharesNewIssues
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

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Name:	us-gaap_DebtInstrumentAxis=amch_SeniorSecuredCreditFacilityMember
Namespace Prefix:
Data Type:	na
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Name:	us-gaap_DebtInstrumentAxis=us-gaap_RevolvingCreditFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	us-gaap_VariableRateAxis=us-gaap_LondonInterbankOfferedRateLIBORMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	us-gaap_VariableRateAxis=us-gaap_FederalFundsEffectiveSwapRateMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	us-gaap_ShortTermDebtTypeAxis=us-gaap_LetterOfCreditMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Namespace Prefix:
Data Type:	na
Balance Type:
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Namespace Prefix:
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