Accordion option

No definition available.

Name:	amk_AccordionOption
Namespace Prefix:	amk_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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

- Definition

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.

+ References

No definition available.

+ Details

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

- Definition

Amount of the cost of borrowed funds accounted for as interest expense for debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
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+ Details

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

- Definition

Description of the terms of a credit facility arrangement. Terms typically include interest rate, collateral required, guarantees required, repayment requirements, and restrictions on use of assets and activities of the entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

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

- Definition

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.

+ References

+ Details

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

- Details

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- Details

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Balance Type:
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- Details

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- Details

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Debt - Additional Information (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
	Jan. 12, 2022	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Dec. 30, 2020
Debt Instrument [Line Items]
Interest expense		$ 1,488	$ 774	$ 2,647	$ 1,545
2020 Credit Agreement \| Bank of Montreal \| Senior Secured Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity						$ 250,000
2020 Credit Agreement \| Bank of Montreal \| 2020 Revolving Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity						250,000
2022 Credit Agreement \| 2022 Term Loans
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 125,000
Line of credit facility, description	The 2022 Term Loans are subject to quarterly amortization payments and will mature on January 12, 2027.
2022 Credit Agreement \| Senior Secured Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 500,000
2022 Credit Agreement \| 2022 Revolving Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity	375,000
Accordion Option	$ 100,000
Minimum \| 2022 Credit Agreement \| 2022 Term Loans \| Base Rate
Debt Instrument [Line Items]
Debt instrument, margin percentage	0.875%
Minimum \| 2022 Credit Agreement \| 2022 Term Loans \| SOFR
Debt Instrument [Line Items]
Debt instrument, margin percentage	1.875%
Maximum \| 2020 Credit Agreement \| Bank of Montreal \| 2020 Revolving Credit Facility
Debt Instrument [Line Items]
Accordion Option						$ 25,000
Maximum \| 2022 Credit Agreement \| 2022 Term Loans \| Base Rate
Debt Instrument [Line Items]
Debt instrument, margin percentage	2.50%
Maximum \| 2022 Credit Agreement \| 2022 Term Loans \| SOFR
Debt Instrument [Line Items]
Debt instrument, margin percentage	3.50%