OPERATING LEASES (Details) $ in Thousands	Dec. 31, 2020 USD ($)
Leases, Operating [Abstract]
2021	$ 350
2022	355
2023	259
2024	8
Total Future Minimum Payments Due	$ 972

Lessee, Operating Lease, Liability, Payments, Net Of Sublease Income, Due

No definition available.

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Lessee, Operating Lease, Liability, Payments, Net Of Sublease Income, Due Next Twelve Months

No definition available.

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Lessee, Operating Lease, Liability, Payments, Net Of Sublease Income, Due Year Four

No definition available.

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Data Type:	xbrli:monetaryItemType
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Lessee, Operating Lease, Liability, Payments, Net Of Sublease Income, Due Year Three

No definition available.

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Namespace Prefix:	ams_
Data Type:	xbrli:monetaryItemType
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Lessee, Operating Lease, Liability, Payments, Net Of Sublease Income, Due Year Two

No definition available.

Name:	ams_LesseeOperatingLeaseLiabilityPaymentsNetOfSubleaseIncomeDueYearTwo
Namespace Prefix:	ams_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

No definition available.

Name:	us-gaap_LeasesOperatingAbstract
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