OPERATING LEASES (Details) $ in Thousands	Dec. 31, 2019 USD ($)
Leases, Operating [Abstract]
2020	$ 319
2021	312
2022	319
2023	225
2024	5
Total Future Minimum Payments Due	$ 1,180

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 Five

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 Four

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 Three

No definition available.

Name:	ams_LesseeOperatingLeaseLiabilityPaymentsNetOfSubleaseIncomeDueYearThree
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
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Period Type:	instant

No definition available.

Name:	us-gaap_LeasesOperatingAbstract
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