Commitments and contingencies line items

No definition available.

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- Definition

The amount of excess insurance deductible.

+ References

No definition available.

+ Details

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Namespace Prefix:	amch_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The number of insurers against which lawsuit was filed.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

The maximum amount of coverage claimed under the policy.

+ References

No definition available.

+ Details

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

- Definition

The amount of excess insurance paid by the primary insurer.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The per share amount of a dividend declared, but not paid, as of the financial reporting date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482913/230-10-50-3

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

The amount recovered from insurance. These recoveries reduce costs and losses that are reported as a separate line item under operating expenses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.3)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483621/220-10-S99-2

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Balance Type:	credit
Period Type:	duration

- Definition

Amount awarded from other party in judgment or settlement of litigation.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of litigation expense, including but not limited to legal, forensic, accounting, and investigative fees.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount charged against operating income increasing loss contingency liability, after adjustments to reduce previously estimated charges.

+ References

+ Details

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

- Definition

Amount of damages paid to the plaintiff in the legal matter.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 450
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483076/450-20-50-1

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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483076/450-20-50-9

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The total number of new claims filed pertaining to a loss contingency during the period.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 450
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (a)
-Publisher FASB
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-Section 50
-Paragraph 9
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483076/450-20-50-9

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Data Type:	xbrli:integerItemType
Balance Type:	na
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- Definition

Cash received for the settlement of litigation during the current period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482740/230-10-45-25

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- Definition

Ratio applied to the conversion of stock split, for example but not limited to, one share converted to two or two shares converted to one.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section S99
-Paragraph 4
-Subparagraph (SAB TOPIC 4.C)
-SubTopic 10
-Topic 505
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480008/505-10-S99-4

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- Details

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- Details

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COMMITMENTS AND CONTINGENCIES (Details) $ / shares in Units, $ in Millions									1 Months Ended	3 Months Ended
	Aug. 28, 2023 USD ($)	Aug. 24, 2023	May 04, 2023 USD ($) item	Apr. 02, 2023	Feb. 20, 2023 item	Jan. 06, 2023 USD ($)	Nov. 30, 2022 USD ($)	Jun. 06, 2022 USD ($)	Mar. 31, 2023 USD ($)	Mar. 31, 2024 USD ($)	Mar. 31, 2023 USD ($)	Sep. 14, 2018 $ / shares
Commitments and contingencies line items
Settlement amount										$ 36.2
Stock split conversion ratio		0.1
Shareholder litigation charge											$ 116.6
Shareholder Litigation
Commitments and contingencies line items
Number of actions \| item					2
Stock split conversion ratio				0.1333
Shareholder litigation charge											126.6
Insurance recoveries									$ 10.0
Settlement amount paid	$ 99.3
Number of insurers against whom lawsuit filed \| item			17
Maximum amount of coverage claimed under policy			$ 80.0
Excess amount deductible			10.0
Amount paid by the primary insurer			$ 5.0
Lao Action
Commitments and contingencies line items
Dividends declared \| $ / shares												$ 1.55
Settlement amount								$ 17.4
Litigatioin fees and expenses							$ 3.4
Amount received from legal settlement						$ 14.0
Estimated Fair Value \| Shareholder Litigation
Commitments and contingencies line items
Shareholder litigation charge											$ 116.6