XML 48 R36.htm IDEA: XBRL DOCUMENT
v3.19.1

INVESTMENT IN EQUITY SECURITIES (Details Textual) - USD ($) | 1 Months Ended | 12 Months Ended
--- | --- | ---
Jun. 30, 2015 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Investments, Fair Value Disclosure |  |  | $ 0 |  |
Other than Temporary Impairment Losses, Investments |  | $ 0 | 579,000 | $ 0 |
Cost Method Investments |  | $ 0 | 0 |  |
Cost-method Investments, Other than Temporary Impairment |  |  |  |  | $ 26,000
Mevion Medical Systems Inc [Member] |  |  |  |  |
Investments, Fair Value Disclosure | $ 600,000 |  |  |  | 579,000
Other than Temporary Impairment Losses, Investments | $ 2,114,000 |  | $ 579,000 |  | $ 2,140,000

X
- Definition Amount, after adjustment, of cost-method investment. Adjustments include, but are not limited to, dividends received in excess of earnings after date of investment that are considered a return of investment and other than temporary impairments. + References No definition available. + Details
Name: | us-gaap_CostMethodInvestments
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition This item represents an other than temporary decline in value that has been recognized against an investment accounted for under the cost method of accounting. The excess of the carrying amount over the fair value of the investment represents the amount of the write down which is or was reflected in earnings. The written down value is a new cost basis with the adjusted value of the investment becoming its new carrying value. Evidence of a loss in value might include, but would not necessarily be limited to, absence of an ability to recover the carrying amount of the investment or inability of the investee to sustain an earnings capacity which would justify the carrying amount of the investment. + References No definition available. + Details
Name: | us-gaap_CostmethodInvestmentsOtherThanTemporaryImpairment
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 8A -URI http://asc.fasb.org/extlink&oid=109979856&loc=SL6284422-111562 + Details
Name: | us-gaap_ImpairmentOfInvestments
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258 + Details
Name: | us-gaap_InvestmentsFairValueDisclosure
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=ams_MevionMedicalSystemsIncMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |