The amount of redemption of debt during the reporting period.

No definition available.

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

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

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+ Details

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

- Definition

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

+ References

+ Details

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

- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

+ References

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Balance Type:	credit
Period Type:	duration

- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

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Period Type:	duration

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- Details

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SUBSEQUENT EVENTS (Details) - USD ($) $ in Millions		12 Months Ended
SUBSEQUENT EVENTS (Details) - USD ($) $ in Millions	Feb. 14, 2022	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Jan. 15, 2021	Oct. 15, 2020	Jul. 31, 2020	Apr. 24, 2020	Apr. 15, 2020
Subsequent Event [Line Items]
Loss on debt extinguishment			$ 14.1	$ (93.6)	$ 16.6
Other expense (income)
Subsequent Event [Line Items]
Loss on debt extinguishment			14.4		$ 16.6
First Lien Notes due 2025
Subsequent Event [Line Items]
Aggregate principal amount									$ 500.0
Stated interest rate (as a percent)				10.50%	10.50%		10.50%	10.50%	10.50%	10.50%
First Lien Notes due 2026
Subsequent Event [Line Items]
Aggregate principal amount			$ 300.0					$ 200.0
Stated interest rate (as a percent)			10.50%	10.50%	10.50%			10.50%
First Lien Toggle Notes due 2026
Subsequent Event [Line Items]
Aggregate principal amount						$ 100.0
Stated interest rate (as a percent)			15.00%	15.00%
Loss on debt extinguishment			$ 14.4
Subsequent Events \| Other expense (income)
Subsequent Event [Line Items]
Loss on debt extinguishment		$ 135.0
Subsequent Events \| First Lien Notes due 2029
Subsequent Event [Line Items]
Aggregate principal amount	$ 950.0
Stated interest rate (as a percent)	7.50%
Subsequent Events \| First Lien Notes due 2025
Subsequent Event [Line Items]
Redemption amount of debt	$ 500.0
Subsequent Events \| First Lien Notes due 2026
Subsequent Event [Line Items]
Redemption amount of debt	300.0
Subsequent Events \| First Lien Toggle Notes due 2026
Subsequent Event [Line Items]
Redemption amount of debt	$ 73.5